PM> Install-Package Spire.PDF 

using Spire.Pdf;
    using System.Drawing;
    
    namespace PDFBackgroundColor
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
    
                //Load a sample PDF file from disk
                pdf.LoadFromFile("input.pdf");
    
                //Loop through the pages in the PDF file
                foreach (PdfPageBase page in pdf.Pages)
                {
                    //Set the background color for each page
                    page.BackgroundColor = Color.Yellow;
    
                    //Set the opacity of the background
                    page.BackgroudOpacity = 0.1f;
                }
    
                //Save the result PDF file
                pdf.SaveToFile("BackgroundColor.pdf");
                pdf.Close();
    
            }
        }
    }

Imports Spire.PDF
    Imports System.Drawing
    
    Namespace PDFBackgroundColor
        Class Program
            Private Shared Sub Main(ByVal args() As String)
    
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument
    
                'Load a sample PDF file from disk
                pdf.LoadFromFile("input.pdf")
    
                'Loop through the pages in the PDF file
                For Each page As PdfPageBase In pdf.Pages
    
                    'Set the background color for each page
                    page.BackgroundColor = Color.Yellow
    
                    'Set the opacity of the background
                    page.BackgroudOpacity = 0.1!
                Next
    
                'Save the result PDF file
                pdf.SaveToFile("BackgroundColor.pdf")
                pdf.Close()
            End Sub
        End Class
    End Namespace

using Spire.Pdf;
    using System.Drawing;
    
    namespace PDFBackgroundImage
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
    
                //Load a sample PDF file from disk
                pdf.LoadFromFile("input.pdf");
    
                //Load an image
                Image background = Image.FromFile("background.png");
    
                //Loop through the pages in the PDF file
                foreach (PdfPageBase page in pdf.Pages)
                {
                    //Set the loaded image as the background image for each page
                    page.BackgroundImage = background;
    
                    //Set the opacity of the background
                    page.BackgroudOpacity = 0.2f;
                }
    
                //Save the result PDF file
                pdf.SaveToFile("BackgroundImage.pdf");
                pdf.Close();
    
            }
        }
    }

Imports Spire.PDF
    Imports System.Drawing
    
    Namespace PDFBackgroundImage
        Class Program
            Private Shared Sub Main(ByVal args() As String)
    
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument
    
                'Load a sample PDF file from disk
                pdf.LoadFromFile("input.pdf")
    
                'Load an image
                Dim background As Image = Image.FromFile("background.png")
    
                'Loop through the pages in the PDF file
                For Each page As PdfPageBase In pdf.Pages
    
                    'Set the loaded image as the background image for each page
                    page.BackgroundImage = background
    
                    'Set the opacity of the background
                    page.BackgroudOpacity = 0.2!
                Next
    
                'Save the result PDF file
                pdf.SaveToFile("BackgroundImage.pdf")
                pdf.Close()
            End Sub
        End Class
    End Namespace

PM> Install-Package Spire.PDF

using Spire.Pdf;
    using Spire.Pdf.Graphics;
    using Spire.Pdf.Graphics.Layer;
    using System.Drawing;
    
    namespace AddLayersToPdf
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance and load a sample PDF file
                PdfDocument pdf = new PdfDocument();
                pdf.LoadFromFile(@"C:\Users\Administrator\Desktop\Sample.pdf");
    
                //Invoke AddLayerWatermark method to add a watermark layer
                AddLayerWatermark(pdf);
    
                //Invoke AddLayerHeader method to add a header layer
                AddLayerHeader(pdf);
    
                //Save to file
                pdf.SaveToFile("AddLayers.pdf");
                pdf.Close();
            }
    
            private static void AddLayerWatermark(PdfDocument doc)
            {
                //Create a layer named "Watermark"
                PdfLayer layer = doc.Layers.AddLayer("Watermark");
    
                //Create a font
                PdfTrueTypeFont font = new PdfTrueTypeFont(new Font("Arial", 48), true);
    
                //Specify the watermark text
                string watermarkText = "CONFIDENTIAL";
    
                //Get text size
                SizeF fontSize = font.MeasureString(watermarkText);
    
                //Calculate two offsets
                float offset1 = (float)(fontSize.Width * System.Math.Sqrt(2) / 4);
                float offset2 = (float)(fontSize.Height * System.Math.Sqrt(2) / 4);
    
                //Get page count
                int pageCount = doc.Pages.Count;
    
                //Declare two variables
                PdfPageBase page;
                PdfCanvas canvas;
    
                //Loop through the pages
                for (int i = 0; (i < pageCount); i++)
                {
                    page = doc.Pages[i];
    
                    //Create a canvas from layer
                    canvas = layer.CreateGraphics(page.Canvas);
                    canvas.TranslateTransform(page.Canvas.Size.Width / 2 - offset1 - offset2, page.Canvas.Size.Height / 2 + offset1 - offset2);
                    canvas.SetTransparency(0.4f);
                    canvas.RotateTransform(-45);
    
                    //Draw sting on the canvas of layer
                    canvas.DrawString(watermarkText, font, PdfBrushes.DarkBlue, 0, 0);
                }
            }
            private static void AddLayerHeader(PdfDocument doc)
            {
                // Create a layer named "Header"
                PdfLayer layer = doc.Layers.AddLayer("Header");
    
                //Get page size
                SizeF size = doc.Pages[0].Size;
    
                //Specify the initial values of X and y
                float x = 90;
                float y = 40;
    
                //Get page count
                int pageCount = doc.Pages.Count;
    
                //Declare two variables
                PdfPageBase page;
                PdfCanvas canvas;
    
                //Loop through the pages
                for (int i = 0; (i < pageCount); i++)
                {
                    //Draw an image on the layer
                    PdfImage pdfImage = PdfImage.FromFile(@"C:\Users\Administrator\Desktop\img.jpg");
                    float width = pdfImage.Width;
                    float height = pdfImage.Height;
                    page = doc.Pages[i];
                    canvas = layer.CreateGraphics(page.Canvas);
                    canvas.DrawImage(pdfImage, x, y, width, height);
    
                    //Draw a line on the layer
                    PdfPen pen = new PdfPen(PdfBrushes.DarkGray, 2);
                    canvas.DrawLine(pen, x, (y + (height + 5)), (size.Width - x), (y + (height + 2)));
                }
            }
        }
    } 

Imports Spire.Pdf
    Imports Spire.Pdf.Graphics
    Imports Spire.Pdf.Graphics.Layer
    Imports System.Drawing
    
    Namespace AddLayersToPdf
        Class Program
            Private Shared Sub Main(ByVal args() As String)
    
                'Create a PdfDocument instance and load a sample PDF file
                Dim pdf As PdfDocument = New PdfDocument
                pdf.LoadFromFile("C:\Users\Administrator\Desktop\Sample.pdf")
    
                'Invoke AddLayerWatermark method to add a watermark layer
                Program.AddLayerWatermark(pdf)
    
                'Invoke AddLayerHeader method to add a header layer
                Program.AddLayerHeader(pdf)
    
                'Save to file
                pdf.SaveToFile("AddLayers.pdf")
                pdf.Close()
            End Sub
    
            Private Shared Sub AddLayerWatermark(ByVal doc As PdfDocument)
    
                'Create a layer named "Watermark"
                Dim layer As PdfLayer = doc.Layers.AddLayer("Watermark")
    
                'Create a font
                Dim font As PdfTrueTypeFont = New PdfTrueTypeFont(New Font("Arial", 48), True)
    
                'Specify the watermark text
                Dim watermarkText As String = "CONFIDENTIAL"
    
                'Get text size
                Dim fontSize As SizeF = font.MeasureString(watermarkText)
    
                'Calculate two offsets
                Dim offset1 As Single = CSng((fontSize.Width * System.Math.Sqrt(2) / 4))
                Dim offset2 As Single = CSng((fontSize.Height * System.Math.Sqrt(2) / 4))
    
                'Get page count
                Dim pageCount As Integer = doc.Pages.Count
    
                'Declare two variables
                Dim page As PdfPageBase
                Dim canvas As PdfCanvas
    
                'Loop through the pages
                Dim i As Integer = 0
                While (i < pageCount)
                    page = doc.Pages(i)
    
                    'Create a canvas from layer
                    canvas = layer.CreateGraphics(page.Canvas)
                    canvas.TranslateTransform(page.Canvas.Size.Width / 2 - offset1 - offset2, page.Canvas.Size.Height / 2 + offset1 - offset2)
                    canvas.SetTransparency(0.4F)
                    canvas.RotateTransform(-45)
    
                    'Draw sting on the canvas of layer
                    canvas.DrawString(watermarkText, font, PdfBrushes.DarkBlue, 0, 0)
                    i = (i + 1)
                    i += 1
                End While
            End Sub
    
            Private Shared Sub AddLayerHeader(ByVal doc As PdfDocument)
    
                ' Create a layer named "Header"
                Dim layer As PdfLayer = doc.Layers.AddLayer("Header")
    
                'Get page size
                Dim size As SizeF = doc.Pages(0).Size
    
                'Specify the initial values of X and y
                Dim x As Single = 90
                Dim y As Single = 40
    
                'Get page count
                Dim pageCount As Integer = doc.Pages.Count
    
                'Declare two variables
                Dim page As PdfPageBase
                Dim canvas As PdfCanvas
    
                'Loop through the pages
                Dim i As Integer = 0
                While (i < pageCount)
    
                    'Draw an image on the layer
                    Dim pdfImage As PdfImage = PdfImage.FromFile("C:\Users\Administrator\Desktop\img.jpg")
                    Dim width As Single = pdfImage.Width
                    Dim height As Single = pdfImage.Height
                    page = doc.Pages(i)
                    canvas = layer.CreateGraphics(page.Canvas)
                    canvas.DrawImage(pdfImage, x, y, width, height)
    
                    'Draw a line on the layer
                    Dim pen As PdfPen = New PdfPen(PdfBrushes.DarkGray, 2)
                    canvas.DrawLine(pen, x, (y + (height + 5)), (size.Width - x), (y + (height + 2)))
                    i += 1
                End While
            End Sub
        End Class
    End Namespace

using Spire.Pdf;
    using Spire.Pdf.Graphics.Layer;
    
    namespace HideLayer
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
    
                //Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf");
    
                //Hide a specified layer by index
                pdf.Layers[0].Visibility = PdfVisibility.Off;
    
                //Hide a specified layer by name
                //pdf.Layers["Watermark"].Visibility = PdfVisibility.Off;
    
                //Save the result document
                pdf.SaveToFile("HideLayer.pdf");
            }
        }
    }

Imports Spire.Pdf
    Imports Spire.Pdf.Graphics.Layer
    
    Namespace HideLayer
        Class Program
            Private Shared Sub Main(ByVal args() As String)
    
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument
    
                'Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf")
    
                'Hide a specified layer by index
                pdf.Layers(0).Visibility = PdfVisibility.Off
    
                'Hide a specified layer by name
                'pdf.Layers["Watermark"].Visibility = PdfVisibility.Off;
    
                'Save the result document
                pdf.SaveToFile("HideLayer.pdf")
            End Sub
        End Class
    End Namespace

using Spire.Pdf;
    
    namespace DeleteLayer
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
    
                //Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf");
    
                //Remove a layer by name
                pdf.Layers.RemoveLayer(("Watermark"));
    
                //Save the result document
                pdf.SaveToFile("DeleteLayer.pdf", FileFormat.PDF);
            }
        }
    }

Imports Spire.Pdf
    
    Namespace DeleteLayer
        Class Program
            Private Shared Sub Main(ByVal args() As String)
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument
    
                'Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf")
    
                'Remove a layer by name
                pdf.Layers.RemoveLayer("Watermark")
    
                'Save the result document
                pdf.SaveToFile("DeleteLayer.pdf", FileFormat.PDF)
            End Sub
        End Class
    End Namespace

PM> Install-Package Spire.PDF

using Spire.Pdf;
    using Spire.Pdf.Graphics;
    using Spire.Pdf.Graphics.Layer;
    using System.Drawing;
    
    namespace AddLayersToPdf
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance and load a sample PDF file
                PdfDocument pdf = new PdfDocument();
                pdf.LoadFromFile(@"C:\Users\Administrator\Desktop\Sample.pdf");
    
                //Invoke AddLayerWatermark method to add a watermark layer
                AddLayerWatermark(pdf);
    
                //Invoke AddLayerHeader method to add a header layer
                AddLayerHeader(pdf);
    
                //Save to file
                pdf.SaveToFile("AddLayers.pdf");
                pdf.Close();
            }
    
            private static void AddLayerWatermark(PdfDocument doc)
            {
                //Create a layer named "Watermark"
                PdfLayer layer = doc.Layers.AddLayer("Watermark");
    
                //Create a font
                PdfTrueTypeFont font = new PdfTrueTypeFont(new Font("Arial", 48), true);
    
                //Specify the watermark text
                string watermarkText = "CONFIDENTIAL";
    
                //Get text size
                SizeF fontSize = font.MeasureString(watermarkText);
    
                //Calculate two offsets
                float offset1 = (float)(fontSize.Width * System.Math.Sqrt(2) / 4);
                float offset2 = (float)(fontSize.Height * System.Math.Sqrt(2) / 4);
    
                //Get page count
                int pageCount = doc.Pages.Count;
    
                //Declare two variables
                PdfPageBase page;
                PdfCanvas canvas;
    
                //Loop through the pages
                for (int i = 0; (i < pageCount); i++)
                {
                    page = doc.Pages[i];
    
                    //Create a canvas from layer
                    canvas = layer.CreateGraphics(page.Canvas);
                    canvas.TranslateTransform(page.Canvas.Size.Width / 2 - offset1 - offset2, page.Canvas.Size.Height / 2 + offset1 - offset2);
                    canvas.SetTransparency(0.4f);
                    canvas.RotateTransform(-45);
    
                    //Draw sting on the canvas of layer
                    canvas.DrawString(watermarkText, font, PdfBrushes.DarkBlue, 0, 0);
                }
            }
            private static void AddLayerHeader(PdfDocument doc)
            {
                // Create a layer named "Header"
                PdfLayer layer = doc.Layers.AddLayer("Header");
    
                //Get page size
                SizeF size = doc.Pages[0].Size;
    
                //Specify the initial values of X and y
                float x = 90;
                float y = 40;
    
                //Get page count
                int pageCount = doc.Pages.Count;
    
                //Declare two variables
                PdfPageBase page;
                PdfCanvas canvas;
    
                //Loop through the pages
                for (int i = 0; (i < pageCount); i++)
                {
                    //Draw an image on the layer
                    PdfImage pdfImage = PdfImage.FromFile(@"C:\Users\Administrator\Desktop\img.jpg");
                    float width = pdfImage.Width;
                    float height = pdfImage.Height;
                    page = doc.Pages[i];
                    canvas = layer.CreateGraphics(page.Canvas);
                    canvas.DrawImage(pdfImage, x, y, width, height);
    
                    //Draw a line on the layer
                    PdfPen pen = new PdfPen(PdfBrushes.DarkGray, 2);
                    canvas.DrawLine(pen, x, (y + (height + 5)), (size.Width - x), (y + (height + 2)));
                }
            }
        }
    } 

Imports Spire.Pdf
    Imports Spire.Pdf.Graphics
    Imports Spire.Pdf.Graphics.Layer
    Imports System.Drawing
    
    Namespace AddLayersToPdf
        Class Program
            Private Shared Sub Main(ByVal args() As String)
    
                'Create a PdfDocument instance and load a sample PDF file
                Dim pdf As PdfDocument = New PdfDocument
                pdf.LoadFromFile("C:\Users\Administrator\Desktop\Sample.pdf")
    
                'Invoke AddLayerWatermark method to add a watermark layer
                Program.AddLayerWatermark(pdf)
    
                'Invoke AddLayerHeader method to add a header layer
                Program.AddLayerHeader(pdf)
    
                'Save to file
                pdf.SaveToFile("AddLayers.pdf")
                pdf.Close()
            End Sub
    
            Private Shared Sub AddLayerWatermark(ByVal doc As PdfDocument)
    
                'Create a layer named "Watermark"
                Dim layer As PdfLayer = doc.Layers.AddLayer("Watermark")
    
                'Create a font
                Dim font As PdfTrueTypeFont = New PdfTrueTypeFont(New Font("Arial", 48), True)
    
                'Specify the watermark text
                Dim watermarkText As String = "CONFIDENTIAL"
    
                'Get text size
                Dim fontSize As SizeF = font.MeasureString(watermarkText)
    
                'Calculate two offsets
                Dim offset1 As Single = CSng((fontSize.Width * System.Math.Sqrt(2) / 4))
                Dim offset2 As Single = CSng((fontSize.Height * System.Math.Sqrt(2) / 4))
    
                'Get page count
                Dim pageCount As Integer = doc.Pages.Count
    
                'Declare two variables
                Dim page As PdfPageBase
                Dim canvas As PdfCanvas
    
                'Loop through the pages
                Dim i As Integer = 0
                While (i < pageCount)
                    page = doc.Pages(i)
    
                    'Create a canvas from layer
                    canvas = layer.CreateGraphics(page.Canvas)
                    canvas.TranslateTransform(page.Canvas.Size.Width / 2 - offset1 - offset2, page.Canvas.Size.Height / 2 + offset1 - offset2)
                    canvas.SetTransparency(0.4F)
                    canvas.RotateTransform(-45)
    
                    'Draw sting on the canvas of layer
                    canvas.DrawString(watermarkText, font, PdfBrushes.DarkBlue, 0, 0)
                    i = (i + 1)
                    i += 1
                End While
            End Sub
    
            Private Shared Sub AddLayerHeader(ByVal doc As PdfDocument)
    
                ' Create a layer named "Header"
                Dim layer As PdfLayer = doc.Layers.AddLayer("Header")
    
                'Get page size
                Dim size As SizeF = doc.Pages(0).Size
    
                'Specify the initial values of X and y
                Dim x As Single = 90
                Dim y As Single = 40
    
                'Get page count
                Dim pageCount As Integer = doc.Pages.Count
    
                'Declare two variables
                Dim page As PdfPageBase
                Dim canvas As PdfCanvas
    
                'Loop through the pages
                Dim i As Integer = 0
                While (i < pageCount)
    
                    'Draw an image on the layer
                    Dim pdfImage As PdfImage = PdfImage.FromFile("C:\Users\Administrator\Desktop\img.jpg")
                    Dim width As Single = pdfImage.Width
                    Dim height As Single = pdfImage.Height
                    page = doc.Pages(i)
                    canvas = layer.CreateGraphics(page.Canvas)
                    canvas.DrawImage(pdfImage, x, y, width, height)
    
                    'Draw a line on the layer
                    Dim pen As PdfPen = New PdfPen(PdfBrushes.DarkGray, 2)
                    canvas.DrawLine(pen, x, (y + (height + 5)), (size.Width - x), (y + (height + 2)))
                    i += 1
                End While
            End Sub
        End Class
    End Namespace

using Spire.Pdf;
    using Spire.Pdf.Graphics.Layer;
    
    namespace HideLayer
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
    
                //Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf");
    
                //Hide a specified layer by index
                pdf.Layers[0].Visibility = PdfVisibility.Off;
    
                //Hide a specified layer by name
                //pdf.Layers["Watermark"].Visibility = PdfVisibility.Off;
    
                //Save the result document
                pdf.SaveToFile("HideLayer.pdf");
            }
        }
    }

Imports Spire.Pdf
    Imports Spire.Pdf.Graphics.Layer
    
    Namespace HideLayer
        Class Program
            Private Shared Sub Main(ByVal args() As String)
    
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument
    
                'Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf")
    
                'Hide a specified layer by index
                pdf.Layers(0).Visibility = PdfVisibility.Off
    
                'Hide a specified layer by name
                'pdf.Layers["Watermark"].Visibility = PdfVisibility.Off;
    
                'Save the result document
                pdf.SaveToFile("HideLayer.pdf")
            End Sub
        End Class
    End Namespace

using Spire.Pdf;
    
    namespace DeleteLayer
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
    
                //Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf");
    
                //Remove a layer by name
                pdf.Layers.RemoveLayer(("Watermark"));
    
                //Save the result document
                pdf.SaveToFile("DeleteLayer.pdf", FileFormat.PDF);
            }
        }
    }

Imports Spire.Pdf
    
    Namespace DeleteLayer
        Class Program
            Private Shared Sub Main(ByVal args() As String)
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument
    
                'Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf")
    
                'Remove a layer by name
                pdf.Layers.RemoveLayer("Watermark")
    
                'Save the result document
                pdf.SaveToFile("DeleteLayer.pdf", FileFormat.PDF)
            End Sub
        End Class
    End Namespace

PM> Install-Package Spire.PDF

using Spire.Pdf;
    using Spire.Pdf.Graphics;
    using Spire.Pdf.Graphics.Layer;
    using System.Drawing;
    
    namespace AddLayersToPdf
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance and load a sample PDF file
                PdfDocument pdf = new PdfDocument();
                pdf.LoadFromFile(@"C:\Users\Administrator\Desktop\Sample.pdf");
    
                //Invoke AddLayerWatermark method to add a watermark layer
                AddLayerWatermark(pdf);
    
                //Invoke AddLayerHeader method to add a header layer
                AddLayerHeader(pdf);
    
                //Save to file
                pdf.SaveToFile("AddLayers.pdf");
                pdf.Close();
            }
    
            private static void AddLayerWatermark(PdfDocument doc)
            {
                //Create a layer named "Watermark"
                PdfLayer layer = doc.Layers.AddLayer("Watermark");
    
                //Create a font
                PdfTrueTypeFont font = new PdfTrueTypeFont(new Font("Arial", 48), true);
    
                //Specify the watermark text
                string watermarkText = "CONFIDENTIAL";
    
                //Get text size
                SizeF fontSize = font.MeasureString(watermarkText);
    
                //Calculate two offsets
                float offset1 = (float)(fontSize.Width * System.Math.Sqrt(2) / 4);
                float offset2 = (float)(fontSize.Height * System.Math.Sqrt(2) / 4);
    
                //Get page count
                int pageCount = doc.Pages.Count;
    
                //Declare two variables
                PdfPageBase page;
                PdfCanvas canvas;
    
                //Loop through the pages
                for (int i = 0; (i < pageCount); i++)
                {
                    page = doc.Pages[i];
    
                    //Create a canvas from layer
                    canvas = layer.CreateGraphics(page.Canvas);
                    canvas.TranslateTransform(page.Canvas.Size.Width / 2 - offset1 - offset2, page.Canvas.Size.Height / 2 + offset1 - offset2);
                    canvas.SetTransparency(0.4f);
                    canvas.RotateTransform(-45);
    
                    //Draw sting on the canvas of layer
                    canvas.DrawString(watermarkText, font, PdfBrushes.DarkBlue, 0, 0);
                }
            }
            private static void AddLayerHeader(PdfDocument doc)
            {
                // Create a layer named "Header"
                PdfLayer layer = doc.Layers.AddLayer("Header");
    
                //Get page size
                SizeF size = doc.Pages[0].Size;
    
                //Specify the initial values of X and y
                float x = 90;
                float y = 40;
    
                //Get page count
                int pageCount = doc.Pages.Count;
    
                //Declare two variables
                PdfPageBase page;
                PdfCanvas canvas;
    
                //Loop through the pages
                for (int i = 0; (i < pageCount); i++)
                {
                    //Draw an image on the layer
                    PdfImage pdfImage = PdfImage.FromFile(@"C:\Users\Administrator\Desktop\img.jpg");
                    float width = pdfImage.Width;
                    float height = pdfImage.Height;
                    page = doc.Pages[i];
                    canvas = layer.CreateGraphics(page.Canvas);
                    canvas.DrawImage(pdfImage, x, y, width, height);
    
                    //Draw a line on the layer
                    PdfPen pen = new PdfPen(PdfBrushes.DarkGray, 2);
                    canvas.DrawLine(pen, x, (y + (height + 5)), (size.Width - x), (y + (height + 2)));
                }
            }
        }
    } 

Imports Spire.Pdf
    Imports Spire.Pdf.Graphics
    Imports Spire.Pdf.Graphics.Layer
    Imports System.Drawing
    
    Namespace AddLayersToPdf
        Class Program
            Private Shared Sub Main(ByVal args() As String)
    
                'Create a PdfDocument instance and load a sample PDF file
                Dim pdf As PdfDocument = New PdfDocument
                pdf.LoadFromFile("C:\Users\Administrator\Desktop\Sample.pdf")
    
                'Invoke AddLayerWatermark method to add a watermark layer
                Program.AddLayerWatermark(pdf)
    
                'Invoke AddLayerHeader method to add a header layer
                Program.AddLayerHeader(pdf)
    
                'Save to file
                pdf.SaveToFile("AddLayers.pdf")
                pdf.Close()
            End Sub
    
            Private Shared Sub AddLayerWatermark(ByVal doc As PdfDocument)
    
                'Create a layer named "Watermark"
                Dim layer As PdfLayer = doc.Layers.AddLayer("Watermark")
    
                'Create a font
                Dim font As PdfTrueTypeFont = New PdfTrueTypeFont(New Font("Arial", 48), True)
    
                'Specify the watermark text
                Dim watermarkText As String = "CONFIDENTIAL"
    
                'Get text size
                Dim fontSize As SizeF = font.MeasureString(watermarkText)
    
                'Calculate two offsets
                Dim offset1 As Single = CSng((fontSize.Width * System.Math.Sqrt(2) / 4))
                Dim offset2 As Single = CSng((fontSize.Height * System.Math.Sqrt(2) / 4))
    
                'Get page count
                Dim pageCount As Integer = doc.Pages.Count
    
                'Declare two variables
                Dim page As PdfPageBase
                Dim canvas As PdfCanvas
    
                'Loop through the pages
                Dim i As Integer = 0
                While (i < pageCount)
                    page = doc.Pages(i)
    
                    'Create a canvas from layer
                    canvas = layer.CreateGraphics(page.Canvas)
                    canvas.TranslateTransform(page.Canvas.Size.Width / 2 - offset1 - offset2, page.Canvas.Size.Height / 2 + offset1 - offset2)
                    canvas.SetTransparency(0.4F)
                    canvas.RotateTransform(-45)
    
                    'Draw sting on the canvas of layer
                    canvas.DrawString(watermarkText, font, PdfBrushes.DarkBlue, 0, 0)
                    i = (i + 1)
                    i += 1
                End While
            End Sub
    
            Private Shared Sub AddLayerHeader(ByVal doc As PdfDocument)
    
                ' Create a layer named "Header"
                Dim layer As PdfLayer = doc.Layers.AddLayer("Header")
    
                'Get page size
                Dim size As SizeF = doc.Pages(0).Size
    
                'Specify the initial values of X and y
                Dim x As Single = 90
                Dim y As Single = 40
    
                'Get page count
                Dim pageCount As Integer = doc.Pages.Count
    
                'Declare two variables
                Dim page As PdfPageBase
                Dim canvas As PdfCanvas
    
                'Loop through the pages
                Dim i As Integer = 0
                While (i < pageCount)
    
                    'Draw an image on the layer
                    Dim pdfImage As PdfImage = PdfImage.FromFile("C:\Users\Administrator\Desktop\img.jpg")
                    Dim width As Single = pdfImage.Width
                    Dim height As Single = pdfImage.Height
                    page = doc.Pages(i)
                    canvas = layer.CreateGraphics(page.Canvas)
                    canvas.DrawImage(pdfImage, x, y, width, height)
    
                    'Draw a line on the layer
                    Dim pen As PdfPen = New PdfPen(PdfBrushes.DarkGray, 2)
                    canvas.DrawLine(pen, x, (y + (height + 5)), (size.Width - x), (y + (height + 2)))
                    i += 1
                End While
            End Sub
        End Class
    End Namespace

using Spire.Pdf;
    using Spire.Pdf.Graphics.Layer;
    
    namespace HideLayer
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
    
                //Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf");
    
                //Hide a specified layer by index
                pdf.Layers[0].Visibility = PdfVisibility.Off;
    
                //Hide a specified layer by name
                //pdf.Layers["Watermark"].Visibility = PdfVisibility.Off;
    
                //Save the result document
                pdf.SaveToFile("HideLayer.pdf");
            }
        }
    }

Imports Spire.Pdf
    Imports Spire.Pdf.Graphics.Layer
    
    Namespace HideLayer
        Class Program
            Private Shared Sub Main(ByVal args() As String)
    
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument
    
                'Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf")
    
                'Hide a specified layer by index
                pdf.Layers(0).Visibility = PdfVisibility.Off
    
                'Hide a specified layer by name
                'pdf.Layers["Watermark"].Visibility = PdfVisibility.Off;
    
                'Save the result document
                pdf.SaveToFile("HideLayer.pdf")
            End Sub
        End Class
    End Namespace

using Spire.Pdf;
    
    namespace DeleteLayer
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
    
                //Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf");
    
                //Remove a layer by name
                pdf.Layers.RemoveLayer(("Watermark"));
    
                //Save the result document
                pdf.SaveToFile("DeleteLayer.pdf", FileFormat.PDF);
            }
        }
    }

Imports Spire.Pdf
    
    Namespace DeleteLayer
        Class Program
            Private Shared Sub Main(ByVal args() As String)
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument
    
                'Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf")
    
                'Remove a layer by name
                pdf.Layers.RemoveLayer("Watermark")
    
                'Save the result document
                pdf.SaveToFile("DeleteLayer.pdf", FileFormat.PDF)
            End Sub
        End Class
    End Namespace

PM> Install-Package Spire.PDF

using Spire.Pdf;
    using Spire.Pdf.Graphics;
    using Spire.Pdf.Graphics.Layer;
    using System.Drawing;
    
    namespace AddLayersToPdf
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance and load a sample PDF file
                PdfDocument pdf = new PdfDocument();
                pdf.LoadFromFile(@"C:\Users\Administrator\Desktop\Sample.pdf");
    
                //Invoke AddLayerWatermark method to add a watermark layer
                AddLayerWatermark(pdf);
    
                //Invoke AddLayerHeader method to add a header layer
                AddLayerHeader(pdf);
    
                //Save to file
                pdf.SaveToFile("AddLayers.pdf");
                pdf.Close();
            }
    
            private static void AddLayerWatermark(PdfDocument doc)
            {
                //Create a layer named "Watermark"
                PdfLayer layer = doc.Layers.AddLayer("Watermark");
    
                //Create a font
                PdfTrueTypeFont font = new PdfTrueTypeFont(new Font("Arial", 48), true);
    
                //Specify the watermark text
                string watermarkText = "CONFIDENTIAL";
    
                //Get text size
                SizeF fontSize = font.MeasureString(watermarkText);
    
                //Calculate two offsets
                float offset1 = (float)(fontSize.Width * System.Math.Sqrt(2) / 4);
                float offset2 = (float)(fontSize.Height * System.Math.Sqrt(2) / 4);
    
                //Get page count
                int pageCount = doc.Pages.Count;
    
                //Declare two variables
                PdfPageBase page;
                PdfCanvas canvas;
    
                //Loop through the pages
                for (int i = 0; (i < pageCount); i++)
                {
                    page = doc.Pages[i];
    
                    //Create a canvas from layer
                    canvas = layer.CreateGraphics(page.Canvas);
                    canvas.TranslateTransform(page.Canvas.Size.Width / 2 - offset1 - offset2, page.Canvas.Size.Height / 2 + offset1 - offset2);
                    canvas.SetTransparency(0.4f);
                    canvas.RotateTransform(-45);
    
                    //Draw sting on the canvas of layer
                    canvas.DrawString(watermarkText, font, PdfBrushes.DarkBlue, 0, 0);
                }
            }
            private static void AddLayerHeader(PdfDocument doc)
            {
                // Create a layer named "Header"
                PdfLayer layer = doc.Layers.AddLayer("Header");
    
                //Get page size
                SizeF size = doc.Pages[0].Size;
    
                //Specify the initial values of X and y
                float x = 90;
                float y = 40;
    
                //Get page count
                int pageCount = doc.Pages.Count;
    
                //Declare two variables
                PdfPageBase page;
                PdfCanvas canvas;
    
                //Loop through the pages
                for (int i = 0; (i < pageCount); i++)
                {
                    //Draw an image on the layer
                    PdfImage pdfImage = PdfImage.FromFile(@"C:\Users\Administrator\Desktop\img.jpg");
                    float width = pdfImage.Width;
                    float height = pdfImage.Height;
                    page = doc.Pages[i];
                    canvas = layer.CreateGraphics(page.Canvas);
                    canvas.DrawImage(pdfImage, x, y, width, height);
    
                    //Draw a line on the layer
                    PdfPen pen = new PdfPen(PdfBrushes.DarkGray, 2);
                    canvas.DrawLine(pen, x, (y + (height + 5)), (size.Width - x), (y + (height + 2)));
                }
            }
        }
    } 

Imports Spire.Pdf
    Imports Spire.Pdf.Graphics
    Imports Spire.Pdf.Graphics.Layer
    Imports System.Drawing
    
    Namespace AddLayersToPdf
        Class Program
            Private Shared Sub Main(ByVal args() As String)
    
                'Create a PdfDocument instance and load a sample PDF file
                Dim pdf As PdfDocument = New PdfDocument
                pdf.LoadFromFile("C:\Users\Administrator\Desktop\Sample.pdf")
    
                'Invoke AddLayerWatermark method to add a watermark layer
                Program.AddLayerWatermark(pdf)
    
                'Invoke AddLayerHeader method to add a header layer
                Program.AddLayerHeader(pdf)
    
                'Save to file
                pdf.SaveToFile("AddLayers.pdf")
                pdf.Close()
            End Sub
    
            Private Shared Sub AddLayerWatermark(ByVal doc As PdfDocument)
    
                'Create a layer named "Watermark"
                Dim layer As PdfLayer = doc.Layers.AddLayer("Watermark")
    
                'Create a font
                Dim font As PdfTrueTypeFont = New PdfTrueTypeFont(New Font("Arial", 48), True)
    
                'Specify the watermark text
                Dim watermarkText As String = "CONFIDENTIAL"
    
                'Get text size
                Dim fontSize As SizeF = font.MeasureString(watermarkText)
    
                'Calculate two offsets
                Dim offset1 As Single = CSng((fontSize.Width * System.Math.Sqrt(2) / 4))
                Dim offset2 As Single = CSng((fontSize.Height * System.Math.Sqrt(2) / 4))
    
                'Get page count
                Dim pageCount As Integer = doc.Pages.Count
    
                'Declare two variables
                Dim page As PdfPageBase
                Dim canvas As PdfCanvas
    
                'Loop through the pages
                Dim i As Integer = 0
                While (i < pageCount)
                    page = doc.Pages(i)
    
                    'Create a canvas from layer
                    canvas = layer.CreateGraphics(page.Canvas)
                    canvas.TranslateTransform(page.Canvas.Size.Width / 2 - offset1 - offset2, page.Canvas.Size.Height / 2 + offset1 - offset2)
                    canvas.SetTransparency(0.4F)
                    canvas.RotateTransform(-45)
    
                    'Draw sting on the canvas of layer
                    canvas.DrawString(watermarkText, font, PdfBrushes.DarkBlue, 0, 0)
                    i = (i + 1)
                    i += 1
                End While
            End Sub
    
            Private Shared Sub AddLayerHeader(ByVal doc As PdfDocument)
    
                ' Create a layer named "Header"
                Dim layer As PdfLayer = doc.Layers.AddLayer("Header")
    
                'Get page size
                Dim size As SizeF = doc.Pages(0).Size
    
                'Specify the initial values of X and y
                Dim x As Single = 90
                Dim y As Single = 40
    
                'Get page count
                Dim pageCount As Integer = doc.Pages.Count
    
                'Declare two variables
                Dim page As PdfPageBase
                Dim canvas As PdfCanvas
    
                'Loop through the pages
                Dim i As Integer = 0
                While (i < pageCount)
    
                    'Draw an image on the layer
                    Dim pdfImage As PdfImage = PdfImage.FromFile("C:\Users\Administrator\Desktop\img.jpg")
                    Dim width As Single = pdfImage.Width
                    Dim height As Single = pdfImage.Height
                    page = doc.Pages(i)
                    canvas = layer.CreateGraphics(page.Canvas)
                    canvas.DrawImage(pdfImage, x, y, width, height)
    
                    'Draw a line on the layer
                    Dim pen As PdfPen = New PdfPen(PdfBrushes.DarkGray, 2)
                    canvas.DrawLine(pen, x, (y + (height + 5)), (size.Width - x), (y + (height + 2)))
                    i += 1
                End While
            End Sub
        End Class
    End Namespace

using Spire.Pdf;
    using Spire.Pdf.Graphics.Layer;
    
    namespace HideLayer
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
    
                //Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf");
    
                //Hide a specified layer by index
                pdf.Layers[0].Visibility = PdfVisibility.Off;
    
                //Hide a specified layer by name
                //pdf.Layers["Watermark"].Visibility = PdfVisibility.Off;
    
                //Save the result document
                pdf.SaveToFile("HideLayer.pdf");
            }
        }
    }

Imports Spire.Pdf
    Imports Spire.Pdf.Graphics.Layer
    
    Namespace HideLayer
        Class Program
            Private Shared Sub Main(ByVal args() As String)
    
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument
    
                'Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf")
    
                'Hide a specified layer by index
                pdf.Layers(0).Visibility = PdfVisibility.Off
    
                'Hide a specified layer by name
                'pdf.Layers["Watermark"].Visibility = PdfVisibility.Off;
    
                'Save the result document
                pdf.SaveToFile("HideLayer.pdf")
            End Sub
        End Class
    End Namespace

using Spire.Pdf;
    
    namespace DeleteLayer
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
    
                //Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf");
    
                //Remove a layer by name
                pdf.Layers.RemoveLayer(("Watermark"));
    
                //Save the result document
                pdf.SaveToFile("DeleteLayer.pdf", FileFormat.PDF);
            }
        }
    }

Imports Spire.Pdf
    
    Namespace DeleteLayer
        Class Program
            Private Shared Sub Main(ByVal args() As String)
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument
    
                'Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf")
    
                'Remove a layer by name
                pdf.Layers.RemoveLayer("Watermark")
    
                'Save the result document
                pdf.SaveToFile("DeleteLayer.pdf", FileFormat.PDF)
            End Sub
        End Class
    End Namespace

PM> Install-Package Spire.PDF

using Spire.Pdf;
    using Spire.Pdf.Graphics;
    using Spire.Pdf.Graphics.Layer;
    using System.Drawing;
    
    namespace AddLayersToPdf
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance and load a sample PDF file
                PdfDocument pdf = new PdfDocument();
                pdf.LoadFromFile(@"C:\Users\Administrator\Desktop\Sample.pdf");
    
                //Invoke AddLayerWatermark method to add a watermark layer
                AddLayerWatermark(pdf);
    
                //Invoke AddLayerHeader method to add a header layer
                AddLayerHeader(pdf);
    
                //Save to file
                pdf.SaveToFile("AddLayers.pdf");
                pdf.Close();
            }
    
            private static void AddLayerWatermark(PdfDocument doc)
            {
                //Create a layer named "Watermark"
                PdfLayer layer = doc.Layers.AddLayer("Watermark");
    
                //Create a font
                PdfTrueTypeFont font = new PdfTrueTypeFont(new Font("Arial", 48), true);
    
                //Specify the watermark text
                string watermarkText = "CONFIDENTIAL";
    
                //Get text size
                SizeF fontSize = font.MeasureString(watermarkText);
    
                //Calculate two offsets
                float offset1 = (float)(fontSize.Width * System.Math.Sqrt(2) / 4);
                float offset2 = (float)(fontSize.Height * System.Math.Sqrt(2) / 4);
    
                //Get page count
                int pageCount = doc.Pages.Count;
    
                //Declare two variables
                PdfPageBase page;
                PdfCanvas canvas;
    
                //Loop through the pages
                for (int i = 0; (i < pageCount); i++)
                {
                    page = doc.Pages[i];
    
                    //Create a canvas from layer
                    canvas = layer.CreateGraphics(page.Canvas);
                    canvas.TranslateTransform(page.Canvas.Size.Width / 2 - offset1 - offset2, page.Canvas.Size.Height / 2 + offset1 - offset2);
                    canvas.SetTransparency(0.4f);
                    canvas.RotateTransform(-45);
    
                    //Draw sting on the canvas of layer
                    canvas.DrawString(watermarkText, font, PdfBrushes.DarkBlue, 0, 0);
                }
            }
            private static void AddLayerHeader(PdfDocument doc)
            {
                // Create a layer named "Header"
                PdfLayer layer = doc.Layers.AddLayer("Header");
    
                //Get page size
                SizeF size = doc.Pages[0].Size;
    
                //Specify the initial values of X and y
                float x = 90;
                float y = 40;
    
                //Get page count
                int pageCount = doc.Pages.Count;
    
                //Declare two variables
                PdfPageBase page;
                PdfCanvas canvas;
    
                //Loop through the pages
                for (int i = 0; (i < pageCount); i++)
                {
                    //Draw an image on the layer
                    PdfImage pdfImage = PdfImage.FromFile(@"C:\Users\Administrator\Desktop\img.jpg");
                    float width = pdfImage.Width;
                    float height = pdfImage.Height;
                    page = doc.Pages[i];
                    canvas = layer.CreateGraphics(page.Canvas);
                    canvas.DrawImage(pdfImage, x, y, width, height);
    
                    //Draw a line on the layer
                    PdfPen pen = new PdfPen(PdfBrushes.DarkGray, 2);
                    canvas.DrawLine(pen, x, (y + (height + 5)), (size.Width - x), (y + (height + 2)));
                }
            }
        }
    } 

Imports Spire.Pdf
    Imports Spire.Pdf.Graphics
    Imports Spire.Pdf.Graphics.Layer
    Imports System.Drawing
    
    Namespace AddLayersToPdf
        Class Program
            Private Shared Sub Main(ByVal args() As String)
    
                'Create a PdfDocument instance and load a sample PDF file
                Dim pdf As PdfDocument = New PdfDocument
                pdf.LoadFromFile("C:\Users\Administrator\Desktop\Sample.pdf")
    
                'Invoke AddLayerWatermark method to add a watermark layer
                Program.AddLayerWatermark(pdf)
    
                'Invoke AddLayerHeader method to add a header layer
                Program.AddLayerHeader(pdf)
    
                'Save to file
                pdf.SaveToFile("AddLayers.pdf")
                pdf.Close()
            End Sub
    
            Private Shared Sub AddLayerWatermark(ByVal doc As PdfDocument)
    
                'Create a layer named "Watermark"
                Dim layer As PdfLayer = doc.Layers.AddLayer("Watermark")
    
                'Create a font
                Dim font As PdfTrueTypeFont = New PdfTrueTypeFont(New Font("Arial", 48), True)
    
                'Specify the watermark text
                Dim watermarkText As String = "CONFIDENTIAL"
    
                'Get text size
                Dim fontSize As SizeF = font.MeasureString(watermarkText)
    
                'Calculate two offsets
                Dim offset1 As Single = CSng((fontSize.Width * System.Math.Sqrt(2) / 4))
                Dim offset2 As Single = CSng((fontSize.Height * System.Math.Sqrt(2) / 4))
    
                'Get page count
                Dim pageCount As Integer = doc.Pages.Count
    
                'Declare two variables
                Dim page As PdfPageBase
                Dim canvas As PdfCanvas
    
                'Loop through the pages
                Dim i As Integer = 0
                While (i < pageCount)
                    page = doc.Pages(i)
    
                    'Create a canvas from layer
                    canvas = layer.CreateGraphics(page.Canvas)
                    canvas.TranslateTransform(page.Canvas.Size.Width / 2 - offset1 - offset2, page.Canvas.Size.Height / 2 + offset1 - offset2)
                    canvas.SetTransparency(0.4F)
                    canvas.RotateTransform(-45)
    
                    'Draw sting on the canvas of layer
                    canvas.DrawString(watermarkText, font, PdfBrushes.DarkBlue, 0, 0)
                    i = (i + 1)
                    i += 1
                End While
            End Sub
    
            Private Shared Sub AddLayerHeader(ByVal doc As PdfDocument)
    
                ' Create a layer named "Header"
                Dim layer As PdfLayer = doc.Layers.AddLayer("Header")
    
                'Get page size
                Dim size As SizeF = doc.Pages(0).Size
    
                'Specify the initial values of X and y
                Dim x As Single = 90
                Dim y As Single = 40
    
                'Get page count
                Dim pageCount As Integer = doc.Pages.Count
    
                'Declare two variables
                Dim page As PdfPageBase
                Dim canvas As PdfCanvas
    
                'Loop through the pages
                Dim i As Integer = 0
                While (i < pageCount)
    
                    'Draw an image on the layer
                    Dim pdfImage As PdfImage = PdfImage.FromFile("C:\Users\Administrator\Desktop\img.jpg")
                    Dim width As Single = pdfImage.Width
                    Dim height As Single = pdfImage.Height
                    page = doc.Pages(i)
                    canvas = layer.CreateGraphics(page.Canvas)
                    canvas.DrawImage(pdfImage, x, y, width, height)
    
                    'Draw a line on the layer
                    Dim pen As PdfPen = New PdfPen(PdfBrushes.DarkGray, 2)
                    canvas.DrawLine(pen, x, (y + (height + 5)), (size.Width - x), (y + (height + 2)))
                    i += 1
                End While
            End Sub
        End Class
    End Namespace

using Spire.Pdf;
    using Spire.Pdf.Graphics.Layer;
    
    namespace HideLayer
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
    
                //Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf");
    
                //Hide a specified layer by index
                pdf.Layers[0].Visibility = PdfVisibility.Off;
    
                //Hide a specified layer by name
                //pdf.Layers["Watermark"].Visibility = PdfVisibility.Off;
    
                //Save the result document
                pdf.SaveToFile("HideLayer.pdf");
            }
        }
    }

Imports Spire.Pdf
    Imports Spire.Pdf.Graphics.Layer
    
    Namespace HideLayer
        Class Program
            Private Shared Sub Main(ByVal args() As String)
    
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument
    
                'Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf")
    
                'Hide a specified layer by index
                pdf.Layers(0).Visibility = PdfVisibility.Off
    
                'Hide a specified layer by name
                'pdf.Layers["Watermark"].Visibility = PdfVisibility.Off;
    
                'Save the result document
                pdf.SaveToFile("HideLayer.pdf")
            End Sub
        End Class
    End Namespace

using Spire.Pdf;
    
    namespace DeleteLayer
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
    
                //Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf");
    
                //Remove a layer by name
                pdf.Layers.RemoveLayer(("Watermark"));
    
                //Save the result document
                pdf.SaveToFile("DeleteLayer.pdf", FileFormat.PDF);
            }
        }
    }

Imports Spire.Pdf
    
    Namespace DeleteLayer
        Class Program
            Private Shared Sub Main(ByVal args() As String)
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument
    
                'Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf")
    
                'Remove a layer by name
                pdf.Layers.RemoveLayer("Watermark")
    
                'Save the result document
                pdf.SaveToFile("DeleteLayer.pdf", FileFormat.PDF)
            End Sub
        End Class
    End Namespace

PM> Install-Package Spire.PDF

using Spire.Pdf;
    using Spire.Pdf.Graphics;
    using Spire.Pdf.Graphics.Layer;
    using System.Drawing;
    
    namespace AddLayersToPdf
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance and load a sample PDF file
                PdfDocument pdf = new PdfDocument();
                pdf.LoadFromFile(@"C:\Users\Administrator\Desktop\Sample.pdf");
    
                //Invoke AddLayerWatermark method to add a watermark layer
                AddLayerWatermark(pdf);
    
                //Invoke AddLayerHeader method to add a header layer
                AddLayerHeader(pdf);
    
                //Save to file
                pdf.SaveToFile("AddLayers.pdf");
                pdf.Close();
            }
    
            private static void AddLayerWatermark(PdfDocument doc)
            {
                //Create a layer named "Watermark"
                PdfLayer layer = doc.Layers.AddLayer("Watermark");
    
                //Create a font
                PdfTrueTypeFont font = new PdfTrueTypeFont(new Font("Arial", 48), true);
    
                //Specify the watermark text
                string watermarkText = "CONFIDENTIAL";
    
                //Get text size
                SizeF fontSize = font.MeasureString(watermarkText);
    
                //Calculate two offsets
                float offset1 = (float)(fontSize.Width * System.Math.Sqrt(2) / 4);
                float offset2 = (float)(fontSize.Height * System.Math.Sqrt(2) / 4);
    
                //Get page count
                int pageCount = doc.Pages.Count;
    
                //Declare two variables
                PdfPageBase page;
                PdfCanvas canvas;
    
                //Loop through the pages
                for (int i = 0; (i < pageCount); i++)
                {
                    page = doc.Pages[i];
    
                    //Create a canvas from layer
                    canvas = layer.CreateGraphics(page.Canvas);
                    canvas.TranslateTransform(page.Canvas.Size.Width / 2 - offset1 - offset2, page.Canvas.Size.Height / 2 + offset1 - offset2);
                    canvas.SetTransparency(0.4f);
                    canvas.RotateTransform(-45);
    
                    //Draw sting on the canvas of layer
                    canvas.DrawString(watermarkText, font, PdfBrushes.DarkBlue, 0, 0);
                }
            }
            private static void AddLayerHeader(PdfDocument doc)
            {
                // Create a layer named "Header"
                PdfLayer layer = doc.Layers.AddLayer("Header");
    
                //Get page size
                SizeF size = doc.Pages[0].Size;
    
                //Specify the initial values of X and y
                float x = 90;
                float y = 40;
    
                //Get page count
                int pageCount = doc.Pages.Count;
    
                //Declare two variables
                PdfPageBase page;
                PdfCanvas canvas;
    
                //Loop through the pages
                for (int i = 0; (i < pageCount); i++)
                {
                    //Draw an image on the layer
                    PdfImage pdfImage = PdfImage.FromFile(@"C:\Users\Administrator\Desktop\img.jpg");
                    float width = pdfImage.Width;
                    float height = pdfImage.Height;
                    page = doc.Pages[i];
                    canvas = layer.CreateGraphics(page.Canvas);
                    canvas.DrawImage(pdfImage, x, y, width, height);
    
                    //Draw a line on the layer
                    PdfPen pen = new PdfPen(PdfBrushes.DarkGray, 2);
                    canvas.DrawLine(pen, x, (y + (height + 5)), (size.Width - x), (y + (height + 2)));
                }
            }
        }
    } 

Imports Spire.Pdf
    Imports Spire.Pdf.Graphics
    Imports Spire.Pdf.Graphics.Layer
    Imports System.Drawing
    
    Namespace AddLayersToPdf
        Class Program
            Private Shared Sub Main(ByVal args() As String)
    
                'Create a PdfDocument instance and load a sample PDF file
                Dim pdf As PdfDocument = New PdfDocument
                pdf.LoadFromFile("C:\Users\Administrator\Desktop\Sample.pdf")
    
                'Invoke AddLayerWatermark method to add a watermark layer
                Program.AddLayerWatermark(pdf)
    
                'Invoke AddLayerHeader method to add a header layer
                Program.AddLayerHeader(pdf)
    
                'Save to file
                pdf.SaveToFile("AddLayers.pdf")
                pdf.Close()
            End Sub
    
            Private Shared Sub AddLayerWatermark(ByVal doc As PdfDocument)
    
                'Create a layer named "Watermark"
                Dim layer As PdfLayer = doc.Layers.AddLayer("Watermark")
    
                'Create a font
                Dim font As PdfTrueTypeFont = New PdfTrueTypeFont(New Font("Arial", 48), True)
    
                'Specify the watermark text
                Dim watermarkText As String = "CONFIDENTIAL"
    
                'Get text size
                Dim fontSize As SizeF = font.MeasureString(watermarkText)
    
                'Calculate two offsets
                Dim offset1 As Single = CSng((fontSize.Width * System.Math.Sqrt(2) / 4))
                Dim offset2 As Single = CSng((fontSize.Height * System.Math.Sqrt(2) / 4))
    
                'Get page count
                Dim pageCount As Integer = doc.Pages.Count
    
                'Declare two variables
                Dim page As PdfPageBase
                Dim canvas As PdfCanvas
    
                'Loop through the pages
                Dim i As Integer = 0
                While (i < pageCount)
                    page = doc.Pages(i)
    
                    'Create a canvas from layer
                    canvas = layer.CreateGraphics(page.Canvas)
                    canvas.TranslateTransform(page.Canvas.Size.Width / 2 - offset1 - offset2, page.Canvas.Size.Height / 2 + offset1 - offset2)
                    canvas.SetTransparency(0.4F)
                    canvas.RotateTransform(-45)
    
                    'Draw sting on the canvas of layer
                    canvas.DrawString(watermarkText, font, PdfBrushes.DarkBlue, 0, 0)
                    i = (i + 1)
                    i += 1
                End While
            End Sub
    
            Private Shared Sub AddLayerHeader(ByVal doc As PdfDocument)
    
                ' Create a layer named "Header"
                Dim layer As PdfLayer = doc.Layers.AddLayer("Header")
    
                'Get page size
                Dim size As SizeF = doc.Pages(0).Size
    
                'Specify the initial values of X and y
                Dim x As Single = 90
                Dim y As Single = 40
    
                'Get page count
                Dim pageCount As Integer = doc.Pages.Count
    
                'Declare two variables
                Dim page As PdfPageBase
                Dim canvas As PdfCanvas
    
                'Loop through the pages
                Dim i As Integer = 0
                While (i < pageCount)
    
                    'Draw an image on the layer
                    Dim pdfImage As PdfImage = PdfImage.FromFile("C:\Users\Administrator\Desktop\img.jpg")
                    Dim width As Single = pdfImage.Width
                    Dim height As Single = pdfImage.Height
                    page = doc.Pages(i)
                    canvas = layer.CreateGraphics(page.Canvas)
                    canvas.DrawImage(pdfImage, x, y, width, height)
    
                    'Draw a line on the layer
                    Dim pen As PdfPen = New PdfPen(PdfBrushes.DarkGray, 2)
                    canvas.DrawLine(pen, x, (y + (height + 5)), (size.Width - x), (y + (height + 2)))
                    i += 1
                End While
            End Sub
        End Class
    End Namespace

using Spire.Pdf;
    using Spire.Pdf.Graphics.Layer;
    
    namespace HideLayer
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
    
                //Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf");
    
                //Hide a specified layer by index
                pdf.Layers[0].Visibility = PdfVisibility.Off;
    
                //Hide a specified layer by name
                //pdf.Layers["Watermark"].Visibility = PdfVisibility.Off;
    
                //Save the result document
                pdf.SaveToFile("HideLayer.pdf");
            }
        }
    }

Imports Spire.Pdf
    Imports Spire.Pdf.Graphics.Layer
    
    Namespace HideLayer
        Class Program
            Private Shared Sub Main(ByVal args() As String)
    
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument
    
                'Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf")
    
                'Hide a specified layer by index
                pdf.Layers(0).Visibility = PdfVisibility.Off
    
                'Hide a specified layer by name
                'pdf.Layers["Watermark"].Visibility = PdfVisibility.Off;
    
                'Save the result document
                pdf.SaveToFile("HideLayer.pdf")
            End Sub
        End Class
    End Namespace

using Spire.Pdf;
    
    namespace DeleteLayer
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
    
                //Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf");
    
                //Remove a layer by name
                pdf.Layers.RemoveLayer(("Watermark"));
    
                //Save the result document
                pdf.SaveToFile("DeleteLayer.pdf", FileFormat.PDF);
            }
        }
    }

Imports Spire.Pdf
    
    Namespace DeleteLayer
        Class Program
            Private Shared Sub Main(ByVal args() As String)
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument
    
                'Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf")
    
                'Remove a layer by name
                pdf.Layers.RemoveLayer("Watermark")
    
                'Save the result document
                pdf.SaveToFile("DeleteLayer.pdf", FileFormat.PDF)
            End Sub
        End Class
    End Namespace

PM> Install-Package Spire.PDF

using Spire.Pdf;
    using Spire.Pdf.Graphics;
    using Spire.Pdf.Graphics.Layer;
    using System.Drawing;
    
    namespace AddLayersToPdf
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance and load a sample PDF file
                PdfDocument pdf = new PdfDocument();
                pdf.LoadFromFile(@"C:\Users\Administrator\Desktop\Sample.pdf");
    
                //Invoke AddLayerWatermark method to add a watermark layer
                AddLayerWatermark(pdf);
    
                //Invoke AddLayerHeader method to add a header layer
                AddLayerHeader(pdf);
    
                //Save to file
                pdf.SaveToFile("AddLayers.pdf");
                pdf.Close();
            }
    
            private static void AddLayerWatermark(PdfDocument doc)
            {
                //Create a layer named "Watermark"
                PdfLayer layer = doc.Layers.AddLayer("Watermark");
    
                //Create a font
                PdfTrueTypeFont font = new PdfTrueTypeFont(new Font("Arial", 48), true);
    
                //Specify the watermark text
                string watermarkText = "CONFIDENTIAL";
    
                //Get text size
                SizeF fontSize = font.MeasureString(watermarkText);
    
                //Calculate two offsets
                float offset1 = (float)(fontSize.Width * System.Math.Sqrt(2) / 4);
                float offset2 = (float)(fontSize.Height * System.Math.Sqrt(2) / 4);
    
                //Get page count
                int pageCount = doc.Pages.Count;
    
                //Declare two variables
                PdfPageBase page;
                PdfCanvas canvas;
    
                //Loop through the pages
                for (int i = 0; (i < pageCount); i++)
                {
                    page = doc.Pages[i];
    
                    //Create a canvas from layer
                    canvas = layer.CreateGraphics(page.Canvas);
                    canvas.TranslateTransform(page.Canvas.Size.Width / 2 - offset1 - offset2, page.Canvas.Size.Height / 2 + offset1 - offset2);
                    canvas.SetTransparency(0.4f);
                    canvas.RotateTransform(-45);
    
                    //Draw sting on the canvas of layer
                    canvas.DrawString(watermarkText, font, PdfBrushes.DarkBlue, 0, 0);
                }
            }
            private static void AddLayerHeader(PdfDocument doc)
            {
                // Create a layer named "Header"
                PdfLayer layer = doc.Layers.AddLayer("Header");
    
                //Get page size
                SizeF size = doc.Pages[0].Size;
    
                //Specify the initial values of X and y
                float x = 90;
                float y = 40;
    
                //Get page count
                int pageCount = doc.Pages.Count;
    
                //Declare two variables
                PdfPageBase page;
                PdfCanvas canvas;
    
                //Loop through the pages
                for (int i = 0; (i < pageCount); i++)
                {
                    //Draw an image on the layer
                    PdfImage pdfImage = PdfImage.FromFile(@"C:\Users\Administrator\Desktop\img.jpg");
                    float width = pdfImage.Width;
                    float height = pdfImage.Height;
                    page = doc.Pages[i];
                    canvas = layer.CreateGraphics(page.Canvas);
                    canvas.DrawImage(pdfImage, x, y, width, height);
    
                    //Draw a line on the layer
                    PdfPen pen = new PdfPen(PdfBrushes.DarkGray, 2);
                    canvas.DrawLine(pen, x, (y + (height + 5)), (size.Width - x), (y + (height + 2)));
                }
            }
        }
    } 

Imports Spire.Pdf
    Imports Spire.Pdf.Graphics
    Imports Spire.Pdf.Graphics.Layer
    Imports System.Drawing
    
    Namespace AddLayersToPdf
        Class Program
            Private Shared Sub Main(ByVal args() As String)
    
                'Create a PdfDocument instance and load a sample PDF file
                Dim pdf As PdfDocument = New PdfDocument
                pdf.LoadFromFile("C:\Users\Administrator\Desktop\Sample.pdf")
    
                'Invoke AddLayerWatermark method to add a watermark layer
                Program.AddLayerWatermark(pdf)
    
                'Invoke AddLayerHeader method to add a header layer
                Program.AddLayerHeader(pdf)
    
                'Save to file
                pdf.SaveToFile("AddLayers.pdf")
                pdf.Close()
            End Sub
    
            Private Shared Sub AddLayerWatermark(ByVal doc As PdfDocument)
    
                'Create a layer named "Watermark"
                Dim layer As PdfLayer = doc.Layers.AddLayer("Watermark")
    
                'Create a font
                Dim font As PdfTrueTypeFont = New PdfTrueTypeFont(New Font("Arial", 48), True)
    
                'Specify the watermark text
                Dim watermarkText As String = "CONFIDENTIAL"
    
                'Get text size
                Dim fontSize As SizeF = font.MeasureString(watermarkText)
    
                'Calculate two offsets
                Dim offset1 As Single = CSng((fontSize.Width * System.Math.Sqrt(2) / 4))
                Dim offset2 As Single = CSng((fontSize.Height * System.Math.Sqrt(2) / 4))
    
                'Get page count
                Dim pageCount As Integer = doc.Pages.Count
    
                'Declare two variables
                Dim page As PdfPageBase
                Dim canvas As PdfCanvas
    
                'Loop through the pages
                Dim i As Integer = 0
                While (i < pageCount)
                    page = doc.Pages(i)
    
                    'Create a canvas from layer
                    canvas = layer.CreateGraphics(page.Canvas)
                    canvas.TranslateTransform(page.Canvas.Size.Width / 2 - offset1 - offset2, page.Canvas.Size.Height / 2 + offset1 - offset2)
                    canvas.SetTransparency(0.4F)
                    canvas.RotateTransform(-45)
    
                    'Draw sting on the canvas of layer
                    canvas.DrawString(watermarkText, font, PdfBrushes.DarkBlue, 0, 0)
                    i = (i + 1)
                    i += 1
                End While
            End Sub
    
            Private Shared Sub AddLayerHeader(ByVal doc As PdfDocument)
    
                ' Create a layer named "Header"
                Dim layer As PdfLayer = doc.Layers.AddLayer("Header")
    
                'Get page size
                Dim size As SizeF = doc.Pages(0).Size
    
                'Specify the initial values of X and y
                Dim x As Single = 90
                Dim y As Single = 40
    
                'Get page count
                Dim pageCount As Integer = doc.Pages.Count
    
                'Declare two variables
                Dim page As PdfPageBase
                Dim canvas As PdfCanvas
    
                'Loop through the pages
                Dim i As Integer = 0
                While (i < pageCount)
    
                    'Draw an image on the layer
                    Dim pdfImage As PdfImage = PdfImage.FromFile("C:\Users\Administrator\Desktop\img.jpg")
                    Dim width As Single = pdfImage.Width
                    Dim height As Single = pdfImage.Height
                    page = doc.Pages(i)
                    canvas = layer.CreateGraphics(page.Canvas)
                    canvas.DrawImage(pdfImage, x, y, width, height)
    
                    'Draw a line on the layer
                    Dim pen As PdfPen = New PdfPen(PdfBrushes.DarkGray, 2)
                    canvas.DrawLine(pen, x, (y + (height + 5)), (size.Width - x), (y + (height + 2)))
                    i += 1
                End While
            End Sub
        End Class
    End Namespace

using Spire.Pdf;
    using Spire.Pdf.Graphics.Layer;
    
    namespace HideLayer
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
    
                //Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf");
    
                //Hide a specified layer by index
                pdf.Layers[0].Visibility = PdfVisibility.Off;
    
                //Hide a specified layer by name
                //pdf.Layers["Watermark"].Visibility = PdfVisibility.Off;
    
                //Save the result document
                pdf.SaveToFile("HideLayer.pdf");
            }
        }
    }

Imports Spire.Pdf
    Imports Spire.Pdf.Graphics.Layer
    
    Namespace HideLayer
        Class Program
            Private Shared Sub Main(ByVal args() As String)
    
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument
    
                'Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf")
    
                'Hide a specified layer by index
                pdf.Layers(0).Visibility = PdfVisibility.Off
    
                'Hide a specified layer by name
                'pdf.Layers["Watermark"].Visibility = PdfVisibility.Off;
    
                'Save the result document
                pdf.SaveToFile("HideLayer.pdf")
            End Sub
        End Class
    End Namespace

using Spire.Pdf;
    
    namespace DeleteLayer
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument instance
                PdfDocument pdf = new PdfDocument();
    
                //Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf");
    
                //Remove a layer by name
                pdf.Layers.RemoveLayer(("Watermark"));
    
                //Save the result document
                pdf.SaveToFile("DeleteLayer.pdf", FileFormat.PDF);
            }
        }
    }

Imports Spire.Pdf
    
    Namespace DeleteLayer
        Class Program
            Private Shared Sub Main(ByVal args() As String)
                'Create a PdfDocument instance
                Dim pdf As PdfDocument = New PdfDocument
    
                'Load a sample PDF document
                pdf.LoadFromFile("AddLayers.pdf")
    
                'Remove a layer by name
                pdf.Layers.RemoveLayer("Watermark")
    
                'Save the result document
                pdf.SaveToFile("DeleteLayer.pdf", FileFormat.PDF)
            End Sub
        End Class
    End Namespace

PM> Install-Package Spire.PDF

using Spire.Pdf;
    using Spire.Pdf.Graphics;
    using System.Drawing;
    
    namespace CreatePdfDocument
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument object
                PdfDocument doc = new PdfDocument();
    
                //Add a page
                PdfPageBase page = doc.Pages.Add(PdfPageSize.A4, new PdfMargins(35f));
    
                //Specify heading text
                String titleText = "What is MySQL";
    
                //Create solid brushes
                PdfSolidBrush titleBrush = new PdfSolidBrush(new PdfRGBColor(Color.Blue));
                PdfSolidBrush paraBrush = new PdfSolidBrush(new PdfRGBColor(Color.Black));
    
                //Create true type fonts
                PdfTrueTypeFont titleFont = new PdfTrueTypeFont(new Font("Times New Roman", 18f, FontStyle.Bold),true);
                PdfTrueTypeFont paraFont = new PdfTrueTypeFont(new Font("Times New Roman", 12f, FontStyle.Regular), true);
    
                //Set the text alignment via PdfStringFormat class
                PdfStringFormat format = new PdfStringFormat();
                format.Alignment = PdfTextAlignment.Center;
    
                //Draw heading on the center of the page
                page.Canvas.DrawString(titleText, titleFont, titleBrush, page.Canvas.ClientSize.Width / 2, 20, format);
    
                //Get paragraph content from a .txt file
                string paraText = File.ReadAllText("C:\\Users\\Administrator\\Desktop\\content.txt");
    
                //Create a PdfTextWidget object to hold the paragrah content
                PdfTextWidget widget = new PdfTextWidget(paraText, paraFont, paraBrush);
    
                //Create a rectangle where the paragraph content will be placed
                RectangleF rect = new RectangleF(0, 50, page.Canvas.ClientSize.Width, page.Canvas.ClientSize.Height);
    
                //Set the PdfLayoutType to Paginate to make the content paginated automatically
                PdfTextLayout layout = new PdfTextLayout();
                layout.Layout = PdfLayoutType.Paginate;
    
                //Draw the widget on the page
                widget.Draw(page, rect, layout);
    
                //Save to file
                doc.SaveToFile("CreatePdfDocument.pdf");
                doc.Dispose();
            }
        }
    }

Imports Spire.Pdf
    Imports Spire.Pdf.Graphics
    Imports System.Drawing
    
    Namespace CreatePdfDocument
        Class Program
            Shared  Sub Main(ByVal args() As String)
                'Create a PdfDocument object
                Dim doc As PdfDocument =  New PdfDocument()
    
                'Add a page
                Dim page As PdfPageBase =  doc.Pages.Add(PdfPageSize.A4,New PdfMargins(35f))
    
                'Specify heading text
                Dim titleText As String =  "What is MySQL"
    
                'Create solid brushes
                Dim titleBrush As PdfSolidBrush =  New PdfSolidBrush(New PdfRGBColor(Color.Blue))
                Dim paraBrush As PdfSolidBrush =  New PdfSolidBrush(New PdfRGBColor(Color.Black))
    
                'Create true type fonts
                Dim titleFont As PdfTrueTypeFont =  New PdfTrueTypeFont(New Font("Times New Roman",18f,FontStyle.Bold),True)
                Dim paraFont As PdfTrueTypeFont =  New PdfTrueTypeFont(New Font("Times New Roman",12f,FontStyle.Regular),True)
    
                'Set the text alignment via PdfStringFormat class
                Dim format As PdfStringFormat =  New PdfStringFormat()
                format.Alignment = PdfTextAlignment.Center
    
                'Draw heading on the center of the page
                page.Canvas.DrawString(titleText, titleFont, titleBrush, page.Canvas.ClientSize.Width / 2, 20, format)
    
                'Get paragraph content from a .txt file
                Dim paraText As String =  File.ReadAllText("C:\\Users\\Administrator\\Desktop\\content.txt")
    
                'Create a PdfTextWidget object to hold the paragrah content
                Dim widget As PdfTextWidget =  New PdfTextWidget(paraText,paraFont,paraBrush)
    
                'Create a rectangle where the paragraph content will be placed
                Dim rect As RectangleF =  New RectangleF(0,50,page.Canvas.ClientSize.Width,page.Canvas.ClientSize.Height)
    
                'Set the PdfLayoutType to Paginate to make the content paginated automatically
                Dim layout As PdfTextLayout =  New PdfTextLayout()
                lay.Layout = PdfLayoutType.Paginate
    
                'Draw the widget on the page
                widget.Draw(page, rect, layout)
    
                'Save to file
                doc.SaveToFile("CreatePdfDocument.pdf")
                doc.Dispose()
            End Sub
        End Class
    End Namespace

PM> Install-Package Spire.PDF

using Spire.Pdf;
    using Spire.Pdf.Graphics;
    using System.Drawing;
    
    namespace CreatePdfDocument
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Create a PdfDocument object
                PdfDocument doc = new PdfDocument();
    
                //Add a page
                PdfPageBase page = doc.Pages.Add(PdfPageSize.A4, new PdfMargins(35f));
    
                //Specify heading text
                String titleText = "What is MySQL";
    
                //Create solid brushes
                PdfSolidBrush titleBrush = new PdfSolidBrush(new PdfRGBColor(Color.Blue));
                PdfSolidBrush paraBrush = new PdfSolidBrush(new PdfRGBColor(Color.Black));
    
                //Create true type fonts
                PdfTrueTypeFont titleFont = new PdfTrueTypeFont(new Font("Times New Roman", 18f, FontStyle.Bold),true);
                PdfTrueTypeFont paraFont = new PdfTrueTypeFont(new Font("Times New Roman", 12f, FontStyle.Regular), true);
    
                //Set the text alignment via PdfStringFormat class
                PdfStringFormat format = new PdfStringFormat();
                format.Alignment = PdfTextAlignment.Center;
    
                //Draw heading on the center of the page
                page.Canvas.DrawString(titleText, titleFont, titleBrush, page.Canvas.ClientSize.Width / 2, 20, format);
    
                //Get paragraph content from a .txt file
                string paraText = File.ReadAllText("C:\\Users\\Administrator\\Desktop\\content.txt");
    
                //Create a PdfTextWidget object to hold the paragrah content
                PdfTextWidget widget = new PdfTextWidget(paraText, paraFont, paraBrush);
    
                //Create a rectangle where the paragraph content will be placed
                RectangleF rect = new RectangleF(0, 50, page.Canvas.ClientSize.Width, page.Canvas.ClientSize.Height);
    
                //Set the PdfLayoutType to Paginate to make the content paginated automatically
                PdfTextLayout layout = new PdfTextLayout();
                layout.Layout = PdfLayoutType.Paginate;
    
                //Draw the widget on the page
                widget.Draw(page, rect, layout);
    
                //Save to file
                doc.SaveToFile("CreatePdfDocument.pdf");
                doc.Dispose();
            }
        }
    }

Imports Spire.Pdf
    Imports Spire.Pdf.Graphics
    Imports System.Drawing
    
    Namespace CreatePdfDocument
        Class Program
            Shared  Sub Main(ByVal args() As String)
                'Create a PdfDocument object
                Dim doc As PdfDocument =  New PdfDocument()
    
                'Add a page
                Dim page As PdfPageBase =  doc.Pages.Add(PdfPageSize.A4,New PdfMargins(35f))
    
                'Specify heading text
                Dim titleText As String =  "What is MySQL"
    
                'Create solid brushes
                Dim titleBrush As PdfSolidBrush =  New PdfSolidBrush(New PdfRGBColor(Color.Blue))
                Dim paraBrush As PdfSolidBrush =  New PdfSolidBrush(New PdfRGBColor(Color.Black))
    
                'Create true type fonts
                Dim titleFont As PdfTrueTypeFont =  New PdfTrueTypeFont(New Font("Times New Roman",18f,FontStyle.Bold),True)
                Dim paraFont As PdfTrueTypeFont =  New PdfTrueTypeFont(New Font("Times New Roman",12f,FontStyle.Regular),True)
    
                'Set the text alignment via PdfStringFormat class
                Dim format As PdfStringFormat =  New PdfStringFormat()
                format.Alignment = PdfTextAlignment.Center
    
                'Draw heading on the center of the page
                page.Canvas.DrawString(titleText, titleFont, titleBrush, page.Canvas.ClientSize.Width / 2, 20, format)
    
                'Get paragraph content from a .txt file
                Dim paraText As String =  File.ReadAllText("C:\\Users\\Administrator\\Desktop\\content.txt")
    
                'Create a PdfTextWidget object to hold the paragrah content
                Dim widget As PdfTextWidget =  New PdfTextWidget(paraText,paraFont,paraBrush)
    
                'Create a rectangle where the paragraph content will be placed
                Dim rect As RectangleF =  New RectangleF(0,50,page.Canvas.ClientSize.Width,page.Canvas.ClientSize.Height)
    
                'Set the PdfLayoutType to Paginate to make the content paginated automatically
                Dim layout As PdfTextLayout =  New PdfTextLayout()
                lay.Layout = PdfLayoutType.Paginate
    
                'Draw the widget on the page
                widget.Draw(page, rect, layout)
    
                'Save to file
                doc.SaveToFile("CreatePdfDocument.pdf")
                doc.Dispose()
            End Sub
        End Class
    End Namespace