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