The sample demonstrates how to delete row in Excel workbook via Spire.XLS.

using Spire.Xls;

namespace RowDelete
{
    class Program
    {
        static void Main(string[] args)
        {
            Workbook workbook = new Workbook();
            workbook.LoadFromFile(@"..\..\..\..\Data\parts.xls");
            Worksheet sheet = workbook.Worksheets[0];
            
            //delete the second row from sheet
            sheet.DeleteRow(2);
           
            //delete the seventh and eighth rows from sheet
            sheet.DeleteRow(7,2);

            workbook.SaveToFile("sample.xls", ExcelVersion.Version97to2003);
            System.Diagnostics.Process.Start(workbook.FileName);
        }
    }
}

Imports Spire.Xls

Namespace RowDelete
	Friend Class Program
		Shared Sub Main(ByVal args() As String)
			Dim workbook As New Workbook()
			workbook.LoadFromFile("..\..\..\..\Data\parts.xls")
			Dim sheet As Worksheet = workbook.Worksheets(0)

			'delete the second row from sheet
			sheet.DeleteRow(2)

			'delete the seventh and eighth rows from sheet
			sheet.DeleteRow(7,2)

			workbook.SaveToFile("sample.xls", ExcelVersion.Version97to2003)
			System.Diagnostics.Process.Start(workbook.FileName)
		End Sub
	End Class
End Namespace

The sample demonstrates how to delete workbook column in Excel workbook via Spire.XLS.

using Spire.Xls;

namespace DeleteColumn
{
    class Program
    {
        static void Main(string[] args)
        {
            Workbook workbook = new Workbook();
            workbook.LoadFromFile(@"..\..\..\..\Data\vendors.xls",ExcelVersion.Version97to2003);
            Worksheet sheet = workbook.Worksheets[0];
 
            //delete the first column of sheet
            sheet.DeleteColumn(1); 

            workbook.SaveToFile("sample.xls", ExcelVersion.Version97to2003);
            System.Diagnostics.Process.Start(workbook.FileName);
        }
    }
}

Imports Spire.Xls

Namespace DeleteColumn
	Friend Class Program
		Shared Sub Main(ByVal args() As String)
			Dim workbook As New Workbook()
			workbook.LoadFromFile("..\..\..\..\Data\vendors.xls",ExcelVersion.Version97to2003)
			Dim sheet As Worksheet = workbook.Worksheets(0)

			'delete the first column of sheet
			sheet.DeleteColumn(1)

			workbook.SaveToFile("sample.xls", ExcelVersion.Version97to2003)
			System.Diagnostics.Process.Start(workbook.FileName)
		End Sub
	End Class
End Namespace

The sample demonstrates how to set row height in Excel workbook via Spire.XLS.

using Spire.Xls;

namespace SetRowHeight
{
    class Program
    {
        static void Main(string[] args)
        {
            Workbook workbook = new Workbook();
            workbook.LoadFromFile(@"..\..\..\..\Data\parts.xls");
            Worksheet sheet = workbook.Worksheets[0];
            
            //set the RowHeight=25 of the first row
            sheet.SetRowHeight(1, 25);

            workbook.SaveToFile("sample.xls", ExcelVersion.Version97to2003);
            System.Diagnostics.Process.Start(workbook.FileName);
        }
    }
}

Imports Spire.Xls

Namespace SetRowHeight
	Friend Class Program
		Shared Sub Main(ByVal args() As String)
			Dim workbook As New Workbook()
			workbook.LoadFromFile("..\..\..\..\Data\parts.xls")
			Dim sheet As Worksheet = workbook.Worksheets(0)

			'set the RowHeight=25 of the first row
			sheet.SetRowHeight(1, 25)

			workbook.SaveToFile("sample.xls", ExcelVersion.Version97to2003)
			System.Diagnostics.Process.Start(workbook.FileName)
		End Sub
	End Class
End Namespace

The sample demonstrates how to hide worksheet row in Excel workbook via Spire.XLS.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using Spire.Xls;

namespace RowHide
{
    class Program
    {
        static void Main(string[] args)
        {
            Workbook workbook = new Workbook();
            workbook.LoadFromFile(@"..\..\..\..\Data\parts.xls");
            Worksheet sheet = workbook.Worksheets[0];

            //hide the fourth row of sheet
            sheet.HideRow(4);

            //hide the seventh row of sheet
            sheet.HideRow(7);

            workbook.SaveToFile("sample.xls", ExcelVersion.Version97to2003);
            System.Diagnostics.Process.Start(workbook.FileName);
        }
    }
}

Imports System
Imports System.Collections.Generic
Imports System.Linq
Imports System.Text

Imports Spire.Xls

Namespace RowHide
	Friend Class Program
		Shared Sub Main(ByVal args() As String)
			Dim workbook As New Workbook()
			workbook.LoadFromFile("..\..\..\..\Data\parts.xls")
			Dim sheet As Worksheet = workbook.Worksheets(0)

			'hide the fourth row of sheet
			sheet.HideRow(4)

			'hide the seventh row of sheet
			sheet.HideRow(7)

			workbook.SaveToFile("sample.xls", ExcelVersion.Version97to2003)
			System.Diagnostics.Process.Start(workbook.FileName)
		End Sub
	End Class
End Namespace

The sample demonstrates how to hide worksheet column in Excel workbook via Spire.XLS.

using Spire.Xls;

namespace HideColumn
{
    class Program
    {
        static void Main(string[] args)
        {
            Workbook workbook = new Workbook();
            workbook.LoadFromFile(@"..\..\..\..\Data\vendors.xls");
            Worksheet sheet = workbook.Worksheets[0];
            
            //hide the first column  of sheet
            sheet.HideColumn(1);

           //hide the sixth column of sheet
            sheet.HideColumn(6);
            
            workbook.SaveToFile("sample.xls", ExcelVersion.Version97to2003);
            System.Diagnostics.Process.Start(workbook.FileName);
        }
    }
}

Imports Spire.Xls

Namespace HideColumn
	Friend Class Program
		Shared Sub Main(ByVal args() As String)
			Dim workbook As New Workbook()
			workbook.LoadFromFile("..\..\..\..\Data\vendors.xls")
			Dim sheet As Worksheet = workbook.Worksheets(0)

			'hide the first column  of sheet
			sheet.HideColumn(1)

		   'hide the sixth column of sheet
			sheet.HideColumn(6)

			workbook.SaveToFile("sample.xls", ExcelVersion.Version97to2003)
			System.Diagnostics.Process.Start(workbook.FileName)
		End Sub
	End Class
End Namespace

The sample demonstrates how to add worksheet in Excel workbook via Spire.XLS.

using System.Drawing;
using System.Data;
using System.Data.OleDb;

using Spire.Xls;

namespace AddSheet
{
    class Program
    {
        static void Main(string[] args)
        {
            Workbook workbook = new Workbook();
            workbook.LoadFromFile(@"..\..\..\..\Data\parts.xls");

            //add one worksheet to workbook
            workbook.CreateEmptySheet("NewSheet");
            
           //set the new sheet's context
            Worksheet sheet = workbook.Worksheets[1];
            string connString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=..\\..\\..\\..\\Data\\database.accdb;Persist Security Info=False;";
            string sqlCountry="select * from vendors";
            DataTable vendor = new DataTable();
            using (OleDbConnection conn = new OleDbConnection(connString))
            {
                OleDbDataAdapter adapter = new OleDbDataAdapter(sqlCountry, conn);
                adapter.Fill(vendor);
            }
            sheet.InsertDataTable(vendor, true, 1, 1);

            //set the style of the new sheet
            sheet.AllocatedRange.AutoFitColumns();
            sheet.Range[1, 1, 1, vendor.Columns.Count].Style.Color = Color.DeepSkyBlue;
            sheet.Range[1, 1, 1, vendor.Columns.Count].Style.Font.IsBold = true;
            sheet.Range[1, 1, 1, vendor.Columns.Count].HorizontalAlignment = HorizontalAlignType.Center;
            sheet.Range[2, 1, vendor.Rows.Count + 1, vendor.Columns.Count].Style.Color = Color.SkyBlue;
            sheet.AllocatedRange.Style.Borders.LineStyle = LineStyleType.Thin;
            sheet.AllocatedRange.Borders[BordersLineType.DiagonalDown].LineStyle = LineStyleType.None;
            sheet.AllocatedRange.Borders[BordersLineType.DiagonalUp].LineStyle = LineStyleType.None;
                 
            workbook.SaveToFile("sample.xls", ExcelVersion.Version97to2003);
            System.Diagnostics.Process.Start(workbook.FileName);
        }
    }
}

Imports System.Drawing
Imports System.Data
Imports System.Data.OleDb

Imports Spire.Xls

Namespace AddSheet
	Class Program
		Private Shared Sub Main(args As String())
			Dim workbook As New Workbook()
			workbook.LoadFromFile("..\..\..\..\Data\parts.xls")

			'add one worksheet to workbook
			workbook.CreateEmptySheet("NewSheet")

			'set the new sheet's context
			Dim sheet As Worksheet = workbook.Worksheets(1)
			Dim connString As String = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=..\..\..\..\Data\database.accdb;Persist Security Info=False;"
			Dim sqlCountry As String = "select * from vendors"
			Dim vendor As New DataTable()
			Using conn As New OleDbConnection(connString)
				Dim adapter As New OleDbDataAdapter(sqlCountry, conn)
				adapter.Fill(vendor)
			End Using
			sheet.InsertDataTable(vendor, True, 1, 1)

			'set the style of the new sheet
			sheet.AllocatedRange.AutoFitColumns()
			sheet.Range(1, 1, 1, vendor.Columns.Count).Style.Color = Color.DeepSkyBlue
			sheet.Range(1, 1, 1, vendor.Columns.Count).Style.Font.IsBold = True
			sheet.Range(1, 1, 1, vendor.Columns.Count).HorizontalAlignment = HorizontalAlignType.Center
			sheet.Range(2, 1, vendor.Rows.Count + 1, vendor.Columns.Count).Style.Color = Color.SkyBlue
			sheet.AllocatedRange.Style.Borders.LineStyle = LineStyleType.Thin
			sheet.AllocatedRange.Borders(BordersLineType.DiagonalDown).LineStyle = LineStyleType.None
			sheet.AllocatedRange.Borders(BordersLineType.DiagonalUp).LineStyle = LineStyleType.None

			workbook.SaveToFile("sample.xls", ExcelVersion.Version97to2003)
			System.Diagnostics.Process.Start(workbook.FileName)
		End Sub
	End Class
End Namespace

The sample demonstrates how to add workbook row via Spire.XLS.

using System.Drawing;
using System.Data;
using System.Data.OleDb;
using Spire.Xls;

namespace AddRow
{
    class Program
    {
        static void Main(string[] args)
        {
            Workbook workbook = new Workbook();
            workbook.LoadFromFile(@"..\..\..\..\Data\parts.xls");
            Worksheet sheet = workbook.Worksheets[0];
            
            //add 3 rows in sheet
            sheet.InsertRow(3,3);
            
            //set the new rows' style
            sheet.Range["A3:G5"].Style.Color = Color.GreenYellow;
            sheet.Range["A3:G5"].Style.Borders.LineStyle = LineStyleType.Thin;
            sheet.Range["A3:G5"].Borders[BordersLineType.DiagonalDown].LineStyle = LineStyleType.None;
            sheet.Range["A3:G5"].Borders[BordersLineType.DiagonalUp].LineStyle = LineStyleType.None;
            sheet.Range["A3:B5"].HorizontalAlignment = HorizontalAlignType.Center;
            sheet.Range["C3:C5"].HorizontalAlignment = HorizontalAlignType.Left;
            sheet.Range["D3:G5"].HorizontalAlignment = HorizontalAlignType.Right;
            
            //add one row in sheet
            sheet.InsertRow(7);
            
            //set the style of the added row
            sheet.Range["A7:G7"].Style.Color = Color.GreenYellow;
            sheet.Range["A7:G7"].Style.Borders.LineStyle = LineStyleType.Thin;
            sheet.Range["A7:G7"].Borders[BordersLineType.DiagonalDown].LineStyle = LineStyleType.None;
            sheet.Range["A7:G7"].Borders[BordersLineType.DiagonalUp].LineStyle = LineStyleType.None;
            sheet.Range["A7:B7"].HorizontalAlignment = HorizontalAlignType.Center;
            sheet.Range["C7"].HorizontalAlignment = HorizontalAlignType.Left;
            sheet.Range["D7:G7"].HorizontalAlignment = HorizontalAlignType.Right;

           //insert data into the new rows
            DataTable parts = GetData();
            for (int i = 3,datarowIndex=8; i <= 5;datarowIndex++, i++)
            {
                for (int j = 1; j <= parts.Columns.Count; j++)
                {
                    sheet.Range[i, j].Value2 = parts.Rows[datarowIndex][j - 1];
                }
            }

            for (int j = 1; j <= parts.Columns.Count; j++)
            {
                sheet.Range[7, j].Value2 = parts.Rows[6][j - 1];
            }
            
           
            workbook.SaveToFile("sample.xls", ExcelVersion.Version97to2003);
            System.Diagnostics.Process.Start(workbook.FileName);
        }

        static private DataTable GetData()
        {
            string connString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=..\\..\\..\\..\\Data\\database.accdb;Persist Security Info=False;";
            string sqlParts = "select * from parts";
            DataTable parts = new DataTable();
            using(OleDbConnection conn=new OleDbConnection(connString))
            {
                OleDbDataAdapter adapter = new OleDbDataAdapter(sqlParts, conn);
                adapter.Fill(parts);
            }
            return parts;
        }
    }
}

Imports System.Drawing
Imports System.Data
Imports System.Data.OleDb
Imports Spire.Xls

Namespace AddRow
	Friend Class Program
		Shared Sub Main(ByVal args() As String)
			Dim workbook As New Workbook()
			workbook.LoadFromFile("..\..\..\..\Data\parts.xls")
			Dim sheet As Worksheet = workbook.Worksheets(0)

			'add 3 rows in sheet
			sheet.InsertRow(3,3)

			'set the new rows' style
			sheet.Range("A3:G5").Style.Color = Color.GreenYellow
			sheet.Range("A3:G5").Style.Borders.LineStyle = LineStyleType.Thin
			sheet.Range("A3:G5").Borders(BordersLineType.DiagonalDown).LineStyle = LineStyleType.None
			sheet.Range("A3:G5").Borders(BordersLineType.DiagonalUp).LineStyle = LineStyleType.None
			sheet.Range("A3:B5").HorizontalAlignment = HorizontalAlignType.Center
			sheet.Range("C3:C5").HorizontalAlignment = HorizontalAlignType.Left
			sheet.Range("D3:G5").HorizontalAlignment = HorizontalAlignType.Right

			'add one row in sheet
			sheet.InsertRow(7)

			'set the style of the added row
			sheet.Range("A7:G7").Style.Color = Color.GreenYellow
			sheet.Range("A7:G7").Style.Borders.LineStyle = LineStyleType.Thin
			sheet.Range("A7:G7").Borders(BordersLineType.DiagonalDown).LineStyle = LineStyleType.None
			sheet.Range("A7:G7").Borders(BordersLineType.DiagonalUp).LineStyle = LineStyleType.None
			sheet.Range("A7:B7").HorizontalAlignment = HorizontalAlignType.Center
			sheet.Range("C7").HorizontalAlignment = HorizontalAlignType.Left
			sheet.Range("D7:G7").HorizontalAlignment = HorizontalAlignType.Right

		   'insert data into the new rows
			Dim parts As DataTable = GetData()
			Dim i As Integer = 3
			Dim datarowIndex As Integer=8
			Do While i <= 5
				For j As Integer = 1 To parts.Columns.Count
					sheet.Range(i, j).Value2 = parts.Rows(datarowIndex)(j - 1)
				Next j
				datarowIndex += 1
				i += 1
			Loop

			For j As Integer = 1 To parts.Columns.Count
				sheet.Range(7, j).Value2 = parts.Rows(6)(j - 1)
			Next j


			workbook.SaveToFile("sample.xls", ExcelVersion.Version97to2003)
			System.Diagnostics.Process.Start(workbook.FileName)
		End Sub

		Private Shared Function GetData() As DataTable
			Dim connString As String = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=..\..\..\..\Data\database.accdb;Persist Security Info=False;"
			Dim sqlParts As String = "select * from parts"
			Dim parts As New DataTable()
			Using conn As New OleDbConnection(connString)
				Dim adapter As New OleDbDataAdapter(sqlParts, conn)
				adapter.Fill(parts)
			End Using
			Return parts
		End Function
	End Class
End Namespace

The sample demonstrates how to Add Column in Excel workbook via Spire.XLS.

using System.Drawing;
using System.Data;
using System.Data.OleDb;
using Spire.Xls;

namespace AddColumn
{
    class Program
    {
        static void Main(string[] args)
        {
            Workbook workbook = new Workbook();
            workbook.LoadFromFile(@"..\..\..\..\Data\parts-column.xls");
            Worksheet sheet = workbook.Worksheets[0];

            //add one column
            sheet.InsertColumn(3);

            //get the data of the new column
            DataColumn dataColumn = GetColumnData(4);

            //insert the data into the new column
            sheet.InsertDataColumn(dataColumn, true, 1, 3);

            //add two columns
            sheet.InsertColumn(5, 2);

            //get the data of the two new columns
            DataColumn dataColumn4 = GetColumnData(5);
            DataColumn dataColumn5 = GetColumnData(6);

            //insert the data into the new columns
            sheet.InsertDataColumn(dataColumn4, true, 1, 5);
            sheet.InsertDataColumn(dataColumn5, true, 1, 6);

            int rowCount = 0;
            rowCount = sheet.Rows.Length;
            //set the added columns's style
            SetFormat(sheet, 3,rowCount);
            SetFormat(sheet, 5,rowCount);
            SetFormat(sheet, 6,rowCount);

            workbook.SaveToFile("sample.xls", ExcelVersion.Version97to2003);
            System.Diagnostics.Process.Start(workbook.FileName);
        }
        static private DataColumn GetColumnData(int columnIndex)
        {
            string connString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=..\\..\\..\\..\\Data\\database.accdb;Persist Security Info=False;";
            DataTable parts = new DataTable();
            using (OleDbConnection conn = new OleDbConnection(connString))
            {
                string sqlParts = "select * from parts";
                OleDbDataAdapter adapter = new OleDbDataAdapter(sqlParts, conn);
                adapter.Fill(parts);
            }
            DataColumn column = parts.Columns[columnIndex];
            return column;
        }

        static private void SetFormat(Worksheet sheet, int columnIndex,int rowCount)
        {
            //set the header style
            sheet.Range[1, columnIndex].Style.Font.IsBold = true;
            sheet.Range[1, columnIndex].Style.Color = Color.DeepSkyBlue;
            sheet.Range[1, columnIndex].HorizontalAlignment = HorizontalAlignType.Center;
            sheet.Range[1, columnIndex].AutoFitColumns();

            //draw the lines
            sheet.Range[1, columnIndex, rowCount-1, columnIndex].Style.Borders.LineStyle = LineStyleType.Thin;
            sheet.Range[1, columnIndex, rowCount-1, columnIndex].Borders[BordersLineType.DiagonalDown].LineStyle = LineStyleType.None;
            sheet.Range[1, columnIndex, rowCount-1, columnIndex].Borders[BordersLineType.DiagonalUp].LineStyle = LineStyleType.None;

            //set the data rows's color
            sheet.Range[2, columnIndex, rowCount-1, columnIndex].Style.Color = Color.SkyBlue;
        }
    }
}

Imports System.Drawing
Imports System.Data
Imports System.Data.OleDb
Imports Spire.Xls

Namespace AddColumn
	Friend Class Program
		Shared Sub Main(ByVal args() As String)
			Dim workbook As New Workbook()
			workbook.LoadFromFile("..\..\..\..\Data\parts-column.xls")
			Dim sheet As Worksheet = workbook.Worksheets(0)

			'add one column
			sheet.InsertColumn(3)

			'get the data of the new column
			Dim dataColumn As DataColumn = GetColumnData(4)

			'insert the data into the new column
			sheet.InsertDataColumn(dataColumn, True, 1, 3)

			'add two columns
			sheet.InsertColumn(5, 2)

			'get the data of the two new columns
			Dim dataColumn4 As DataColumn = GetColumnData(5)
			Dim dataColumn5 As DataColumn = GetColumnData(6)

			'insert the data into the new columns
			sheet.InsertDataColumn(dataColumn4, True, 1, 5)
			sheet.InsertDataColumn(dataColumn5, True, 1, 6)

			Dim rowCount As Integer = 0
			rowCount = sheet.Rows.Length
			'set the added columns's style
			SetFormat(sheet, 3,rowCount)
			SetFormat(sheet, 5,rowCount)
			SetFormat(sheet, 6,rowCount)

			workbook.SaveToFile("sample.xls", ExcelVersion.Version97to2003)
			System.Diagnostics.Process.Start(workbook.FileName)
		End Sub
		Private Shared Function GetColumnData(ByVal columnIndex As Integer) As DataColumn
			Dim connString As String = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=..\..\..\..\Data\database.accdb;Persist Security Info=False;"
			Dim parts As New DataTable()
			Using conn As New OleDbConnection(connString)
				Dim sqlParts As String = "select * from parts"
				Dim adapter As New OleDbDataAdapter(sqlParts, conn)
				adapter.Fill(parts)
			End Using
			Dim column As DataColumn = parts.Columns(columnIndex)
			Return column
		End Function

		Private Shared Sub SetFormat(ByVal sheet As Worksheet, ByVal columnIndex As Integer, ByVal rowCount As Integer)
			'set the header style
			sheet.Range(1, columnIndex).Style.Font.IsBold = True
			sheet.Range(1, columnIndex).Style.Color = Color.DeepSkyBlue
			sheet.Range(1, columnIndex).HorizontalAlignment = HorizontalAlignType.Center
			sheet.Range(1, columnIndex).AutoFitColumns()

			'draw the lines
			sheet.Range(1, columnIndex, rowCount-1, columnIndex).Style.Borders.LineStyle = LineStyleType.Thin
			sheet.Range(1, columnIndex, rowCount-1, columnIndex).Borders(BordersLineType.DiagonalDown).LineStyle = LineStyleType.None
			sheet.Range(1, columnIndex, rowCount-1, columnIndex).Borders(BordersLineType.DiagonalUp).LineStyle = LineStyleType.None

			'set the data rows's color
			sheet.Range(2, columnIndex, rowCount-1, columnIndex).Style.Color = Color.SkyBlue
		End Sub
	End Class
End Namespace

using Spire.Xls;

namespace CharacterFont
{
    class Program
    {
        static void Main(string[] args)
        {
            Workbook workbook = new Workbook();
            workbook.LoadFromFile(@"..\..\..\..\Data\Blank.xls",ExcelVersion.Version97to2003);
            Worksheet worksheet = workbook.Worksheets[0];

            //set the font of Range["A1"]
            worksheet.Range["A1"].Text = "BaTang";
            worksheet.Range["A1"].Style.Font.FontName = "BaTang";

            //set the font of Range["A2"]
            worksheet.Range["A2"].Text = "Cooper Black";
            worksheet.Range["A2"].Style.Font.FontName = "Cooper Black";
            worksheet.Range["A2"].Style.Font.Size = 14;

            //set the font of Range["A3"]
            worksheet.Range["A3"].Text = "Gulim";
            worksheet.Range["A3"].Style.Font.FontName = "Gulim";
            worksheet.Range["A3"].Style.Font.Size = 17;

            //set the font of Range["A4"]
            worksheet.Range["A4"].Text = "Freestyle Script";
            worksheet.Range["A4"].Style.Font.FontName = "Freestyle Script";
            worksheet.Range["A4"].Style.Font.Size = 17;

            //set the font of Range["A5"]
            worksheet.Range["A5"].Text = "Felix Titling";
            worksheet.Range["A5"].Style.Font.FontName = "Felix Titling";
            worksheet.Range["A5"].Style.Font.Size = 17;

            //set the font of Range["A6"]
            worksheet.Range["A6"].Text = "Eras Bold ITC";
            worksheet.Range["A6"].Style.Font.FontName = "Eras Bold ITC";
            worksheet.Range["A6"].Style.Font.Size = 17;

            //set the font of Range["A7"]
            worksheet.Range["A7"].Text = "Tempus Sans ITC";
            worksheet.Range["A7"].Style.Font.FontName = "Tempus Sans ITC";
            worksheet.Range["A7"].Style.Font.Size = 17;

            //set the font of Range["A8"]
            worksheet.Range["A8"].Text = "STENCIL";
            worksheet.Range["A8"].Style.Font.FontName = "STENCIL";
            worksheet.Range["A8"].Style.Font.Size = 17;

            worksheet.AutoFitColumn(1);

            workbook.SaveToFile("sample.xls", ExcelVersion.Version97to2003);
            System.Diagnostics.Process.Start(workbook.FileName);
  
        }
    }
}

Imports Spire.Xls

Namespace CharacterFont
	Friend Class Program
		Shared Sub Main(ByVal args() As String)
			Dim workbook As New Workbook()
			workbook.LoadFromFile("..\..\..\..\Data\Blank.xls",ExcelVersion.Version97to2003)
			Dim worksheet As Worksheet = workbook.Worksheets(0)

			'set the font of Range["A1"]
			worksheet.Range("A1").Text = "BaTang"
			worksheet.Range("A1").Style.Font.FontName = "BaTang"

			'set the font of Range["A2"]
			worksheet.Range("A2").Text = "Cooper Black"
			worksheet.Range("A2").Style.Font.FontName = "Cooper Black"
			worksheet.Range("A2").Style.Font.Size = 14

			'set the font of Range["A3"]
			worksheet.Range("A3").Text = "Gulim"
			worksheet.Range("A3").Style.Font.FontName = "Gulim"
			worksheet.Range("A3").Style.Font.Size = 17

			'set the font of Range["A4"]
			worksheet.Range("A4").Text = "Freestyle Script"
			worksheet.Range("A4").Style.Font.FontName = "Freestyle Script"
			worksheet.Range("A4").Style.Font.Size = 17

			'set the font of Range["A5"]
			worksheet.Range("A5").Text = "Felix Titling"
			worksheet.Range("A5").Style.Font.FontName = "Felix Titling"
			worksheet.Range("A5").Style.Font.Size = 17

			'set the font of Range["A6"]
			worksheet.Range("A6").Text = "Eras Bold ITC"
			worksheet.Range("A6").Style.Font.FontName = "Eras Bold ITC"
			worksheet.Range("A6").Style.Font.Size = 17

			'set the font of Range["A7"]
			worksheet.Range("A7").Text = "Tempus Sans ITC"
			worksheet.Range("A7").Style.Font.FontName = "Tempus Sans ITC"
			worksheet.Range("A7").Style.Font.Size = 17

			'set the font of Range["A8"]
			worksheet.Range("A8").Text = "STENCIL"
			worksheet.Range("A8").Style.Font.FontName = "STENCIL"
			worksheet.Range("A8").Style.Font.Size = 17

			worksheet.AutoFitColumn(1)

			workbook.SaveToFile("sample.xls", ExcelVersion.Version97to2003)
			System.Diagnostics.Process.Start(workbook.FileName)

		End Sub
	End Class
End Namespace

The sample demonstrates how to encrypt Excel workbook via Spire.XLS.

using Spire.Xls;

namespace Encrypt
{
    class Program
    {
        static void Main(string[] args)
        {
            //create workbook
            Workbook workbook =new Workbook ();
            Worksheet worksheet = workbook.Worksheets[0];
            workbook.LoadFromFile(@"..\..\..\..\Data\employee.xls",ExcelVersion.Version97to2003);
            
            //encrypt the workbook
            workbook.Protect("iceblue");

            workbook.SaveToFile("sample.xls", ExcelVersion.Version97to2003);
            System.Diagnostics.Process.Start(workbook.FileName);                     
        }
    }
}

Imports Spire.Xls

Namespace Encrypt
	Friend Class Program
		Shared Sub Main(ByVal args() As String)
			'create workbook
			Dim workbook As New Workbook()
			Dim worksheet As Worksheet = workbook.Worksheets(0)
			workbook.LoadFromFile("..\..\..\..\Data\employee.xls",ExcelVersion.Version97to2003)

			'encrypt the workbook
			workbook.Protect("iceblue")

			workbook.SaveToFile("sample.xls", ExcelVersion.Version97to2003)
			System.Diagnostics.Process.Start(workbook.FileName)
		End Sub
	End Class
End Namespace