mergin cells in datagridview vb.net

Imports System.Collections.Generic

Imports System.ComponentModel

Imports System.Data

Imports System.Drawing

Imports System.Text

Imports System.Windows.Forms

Imports System.Diagnostics

Imports System.Drawing.Drawing2D

Namespace DataGridView_MergeDemo

Public Class HMergedCell

Inherits DataGridViewTextBoxCell

Private m_nLeftColumn As Integer = 0

Private m_nRightColumn As Integer = 0

''' 

''' Column Index of the left-most cell to be merged.

''' This cell controls the merged text.

''' 

Public Property LeftColumn() As Integer

Get

        Return m_nLeftColumn

End Get

Set

        m_nLeftColumn = value

End Set

        End Property

''' 

''' Column Index of the right-most cell to be merged

''' 

Public Property RightColumn() As Integer

Get

        Return m_nRightColumn

End Get

        Set

        m_nRightColumn = value

        End Set

End Property

Protected Overrides Sub Paint(graphics 

As Graphics, 

clipBounds As Rectangle, cellBounds 

As Rectangle, rowIndex 

As Integer, 

cellState As DataGridViewElementStates, value 

As Object, _

formattedValue As Object, errorText As String,

 cellStyle As DataGridViewCellStyle, 

advancedBorderStyle As 

DataGridViewAdvancedBorderStyle,

 paintParts As 

DataGridViewPaintParts)

Try

Dim mergeindex As Integer = 

ColumnIndex - m_nLeftColumn

Dim i As Integer

Dim nWidth As Integer

Dim nWidthLeft As Integer

Dim strText As String

Dim pen As New Pen(Brushes.Black)

' Draw the background

graphics.FillRectangle(New SolidBrush

(SystemColors.Control),

 cellBounds)

' Draw the separator for rows

graphics.DrawLine(New Pen(New SolidBrush

(SystemColors.ControlDark)), cellBounds.Left, 

cellBounds.Bottom - 1, cellBounds.Right,

 cellBounds.Bottom - 1)

' Draw the right vertical line for the cell

If ColumnIndex = m_nRightColumn Then

graphics.DrawLine(New Pen(New SolidBrush

(SystemColors.ControlDark)), cellBounds.Right - 1,

 cellBounds.Top, cellBounds.Right - 1,

 cellBounds.Bottom)

End If

' Draw the text

Dim rectDest As RectangleF = RectangleF.Empty

Dim sf As New StringFormat()

sf.Alignment = StringAlignment.Center

sf.LineAlignment = StringAlignment.Center

sf.Trimming = StringTrimming.EllipsisCharacter

' Determine the total width of the merged cell

        nWidth = 0

For i = m_nLeftColumn To m_nRightColumn

nWidth += Me.OwningRow.Cells(i).Size.Width

Next

' Determine the width before the current cell.

nWidthLeft = 0

For i = m_nLeftColumn To ColumnIndex - 1

nWidthLeft += Me.OwningRow.Cells(i).Size.Width

Next

' Retrieve the text to be displayed

strText = Me.OwningRow.Cells(m_nLeftColumn).

Value.ToString()

rectDest = New RectangleF

(cellBounds.Left - nWidthLeft, 

cellBounds.Top, nWidth, cellBounds.Height)

graphics.DrawString(strText, New Font("Arial", 10, 

FontStyle.Regular), Brushes.Black, rectDest, sf)

Catch ex As Exception

Trace.WriteLine(ex.ToString())

End Try

End Sub

        End Class

        ' class

End Namespace