Line annotation appears as a straight line on PDF page, we can use it to insert text or give directions to readers. When moving onto the line annotation, it will display a pop up window with the comment text we added. This article introduces how to add a line annotation to PDF document programmatically using Spire.PDF and C#.
Code snippet:
Step 1: Create a PDF document and add a new page.
PdfDocument document = new PdfDocument(); PdfPageBase page = document.Pages.Add();
Step 2: Create a line annotation using the PdfLineAnnotation(int[] linePoints, string text) constructor.
int[] linePoints = new int[] { 100, 450, 180, 450 }; PdfLineAnnotation lineAnnotation = new PdfLineAnnotation(linePoints, "Comment Text");
Step 3: Set the properties of the line annotation.
//Set the line border lineAnnotation.lineBorder.BorderStyle = PdfBorderStyle.Solid; lineAnnotation.lineBorder.BorderWidth = 1; //Set the line intent lineAnnotation.LineIntent = PdfLineIntent.LineDimension; //Set the line style lineAnnotation.BeginLineStyle = PdfLineEndingStyle.Butt; lineAnnotation.EndLineStyle = PdfLineEndingStyle.Diamond; lineAnnotation.Flags = PdfAnnotationFlags.Default; //Set the line color lineAnnotation.InnerLineColor = new PdfRGBColor(Color.Green); lineAnnotation.BackColor = new PdfRGBColor(Color.Green); //Set the leader line lineAnnotation.LeaderLineExt = 0; lineAnnotation.LeaderLine = 0;
Step 4: Add the line annotation to the page.
page.Annotations.Add(lineAnnotation);
Step 5: Save the document.
document.SaveToFile("LineAnnotation.pdf");
Screenshot:
Full code:
using Spire.Pdf; using Spire.Pdf.Annotations; using System.Drawing; using Spire.Pdf.Graphics; using Spire.Pdf.Fields; namespace Add_line_annotation_to_PDF { class Program { static void Main(string[] args) { //Create a PDF document and add a new page PdfDocument document = new PdfDocument(); PdfPageBase page = document.Pages.Add(); int[] linePoints = new int[] { 100, 450, 180, 450 }; //Create a line annotation PdfLineAnnotation lineAnnotation = new PdfLineAnnotation(linePoints, "Comment Text"); //Set the line border lineAnnotation.lineBorder.BorderStyle = PdfBorderStyle.Solid; lineAnnotation.lineBorder.BorderWidth = 1; //Set the line intent lineAnnotation.LineIntent = PdfLineIntent.LineDimension; //Set the line style lineAnnotation.BeginLineStyle = PdfLineEndingStyle.Butt; lineAnnotation.EndLineStyle = PdfLineEndingStyle.Diamond; lineAnnotation.Flags = PdfAnnotationFlags.Default; //Set the line color lineAnnotation.InnerLineColor = new PdfRGBColor(Color.Green); lineAnnotation.BackColor = new PdfRGBColor(Color.Green); //Set the leader line lineAnnotation.LeaderLineExt = 0; lineAnnotation.LeaderLine = 0; //Add the line annotation to the page page.Annotations.Add(lineAnnotation); //Save the document document.SaveToFile("LineAnnotation.pdf"); } } }