How can i merge two Cells Of Datagridview control in VB.net.

Question

Hello Everybody,

I am a vb 6.0 Developer and now turn into vb.net.

i study the datagridview control. i insert the value in all cells successfully at run-time which i want.

But now My Major Problem is that i want to Merge Two Cells of DataGridView Control.

i m not having any idea of that one.

Is it possible?.

If yes then plz reply me with code or if there is a property of merging two  cell  then also respond me.

Thanks a lot....

Dharmchand Dhingra.......
 

Answer 1

Hi Dharmchand,

Windows Forms DataGridView control has no related properties or methods to merge cells. But you can use Graphics.DrawLine and Graphics.DrawString methods to draw the effect in DataGridView.CellPainting event.

1 Code sample: Vertically merge cells in DataGridView

Imports System.Data.OleDb

Public Class Form1

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

Dim con As OleDbConnection = New OleDbConnection("Provider=Microsoft.jet.oledb.4.0;data source=D:\myDB.mdb")

Dim cmd As OleDbCommand = New OleDbCommand("SELECT * FROM Users", con)

con.Open()

Dim myDA As OleDbDataAdapter = New OleDbDataAdapter(cmd)

Dim myDataSet As DataSet = New DataSet()

myDA.Fill(myDataSet, "MyTable")

DataGridView1.DataSource = myDataSet.Tables("MyTable").DefaultView

con.Close()

con = Nothing

End Sub

'e.g. Vertically merge the same cells of the fourth column

Private Sub DataGridView1_CellPainting(ByVal sender As System.Object, ByVal e As System.Windows.Forms.DataGridViewCellPaintingEventArgs) Handles DataGridView1.CellPainting

If e.ColumnIndex = 3 AndAlso e.RowIndex <> -1 Then

Using gridBrush As Brush = New SolidBrush(Me.DataGridView1.GridColor), backColorBrush As Brush = New SolidBrush(e.CellStyle.BackColor)

Using gridLinePen As Pen = New Pen(gridBrush)

' Clear cell

e.Graphics.FillRectangle(backColorBrush, e.CellBounds)

' Draw line (bottom border and right border of current cell)

'If next row cell has different content, only draw bottom border line of current cell

If e.RowIndex < DataGridView1.Rows.Count - 2 AndAlso DataGridView1.Rows(e.RowIndex + 1).Cells(e.ColumnIndex).Value.ToString() <> e.Value.ToString() Then

e.Graphics.DrawLine(gridLinePen, e.CellBounds.Left, e.CellBounds.Bottom - 1, e.CellBounds.Right - 1, e.CellBounds.Bottom - 1)

End If

' Draw right border line of current cell

e.Graphics.DrawLine(gridLinePen, e.CellBounds.Right - 1, e.CellBounds.Top, e.CellBounds.Right - 1, e.CellBounds.Bottom)

' draw/fill content in current cell, and fill only one cell of multiple same cells

If Not e.Value Is Nothing Then

If e.RowIndex > 0 AndAlso DataGridView1.Rows(e.RowIndex - 1).Cells(e.ColumnIndex).Value.ToString() = e.Value.ToString() Then

Else

e.Graphics.DrawString(CType(e.Value, String), e.CellStyle.Font, Brushes.Black, e.CellBounds.X + 2, e.CellBounds.Y + 5, StringFormat.GenericDefault)

End If

End If

e.Handled = True

End Using

End Using

End If

End Sub

End Class

Illustration:


2 Cose sample: Horizontally merge cells in DataGridView
Another sample: http://www.codeguru.com/forum/showthread.php?p=1537635#post1537635

It provides a demo project: DataGridView_MergeDemo.zip

Here are two helpful tools:
1. Instant VB: C# to VB converter
The tool can convert entire C# project to corresponding VB.NET project, also can convert code snippet.
2. Convert C# code to VB.NET code by means of this Code Translator tool.

Best regards,
Martin Xie

Answer 2

can this be done vertically? like this:

Answer 3

Hi mmel_g,

Actually, that code sample in my previous post demonstrates how to vertically merge cells in DataGridView.

I have modified my post. Please check it.

Best regards,
Martin Xie

Answer 4

good post. 

The example worked great except I need to  be able to select one of the merged items.  is there any way to do that?

Answer 5

Hiii,

Can u please provide datagridview horizontal mergecell vb.net code,

Regards,
Firoz.

Answer 6

Excellent code thanks.

I think there's a minor bug in the line drawing, e.RowIndex < DataGridView1.Rows.Count - 2 should be . . .-1

otherwise the line isn't drawn if they are the bottom two rows in the grid.

Any insights into selecting 'through' the merged cells to the underlying rows would be welcomed here too.

So far I've added this code:

  If dgResults.Rows(e.RowIndex).Selected Then

                ourbackcolor = e.CellStyle.SelectionBackColor

            Else

                ourbackcolor = e.CellStyle.BackColor

            End If

            Using gridBrush As Brush = New SolidBrush(Me.dgResults.GridColor), backColorBrush As Brush = New SolidBrush(ourbackcolor) . . ..

This will display the highlight across the row - not 100% ideal, but IMHO better than nothing.

pg

Answer 7

Hi
     Good code snipet
If e.RowIndex < DataGridView1.Rows.Count - 2 AndAlso DataGridView1.Rows(e.RowIndex + 1).Cells(e.ColumnIndex).Value.ToString() <> e.Value.ToString() Then
                        e.Graphics.DrawLine(gridLinePen, e.CellBounds.Left, e.CellBounds.Bottom - 1, e.CellBounds.Right - 1, e.CellBounds.Bottom - 1)

End If

it show the nullReference Exception in e.value it has nothing how to fix this

and one more doubt

i want to merge row wise also and in the merged cell i want to place a checkbox

please give me a code

Answer 8

Suppose one want to merge Cell 2 and 3 in Row 0 of a Datagrid(dg_ESC) then type following code in Cell Painting event of the Datagrid

Private Sub dg_ESC_CellPainting(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellPaintingEventArgs) Handles dg_ESC.CellPainting

If e.RowIndex = 0 AndAlso (e.ColumnIndex = 2 Or e.ColumnIndex = 3) Then

Using gridBrush As Brush = New SolidBrush(Me.dg_ESC.GridColor), backColorBrush As Brush = New SolidBrush(e.CellStyle.BackColor)

Using gridLinePen As Pen = New Pen(gridBrush)

' Clear cell

e.Graphics.FillRectangle(backColorBrush, e.CellBounds)

'Bottom line drawing

e.Graphics.DrawLine(gridLinePen, e.CellBounds.Left, e.CellBounds.Bottom - 1, e.CellBounds.Right - 1, e.CellBounds.Bottom - 1)

'top line drawing

e.Graphics.DrawLine(gridLinePen, e.CellBounds.Left, e.CellBounds.Top, e.CellBounds.Right - 1, e.CellBounds.Top)

'Drawing Right line

If e.ColumnIndex = 3 Then

e.Graphics.DrawLine(gridLinePen, e.CellBounds.Right - 1, e.CellBounds.Top, e.CellBounds.Right - 1, e.CellBounds.Bottom)

End If

'Inserting text

If e.ColumnIndex = 3 Then

e.Graphics.DrawString(CType(e.Value, String), e.CellStyle.Font, Brushes.Black, e.CellBounds.X - (e.CellBounds.X / 4), e.CellBounds.Y + 5)

End If

e.Handled = True

End Using

End Using

End If

This solve's the problem...

Thanking

Rakesh Sharma,

Jodhpur INDIA

Answer 9

Hi to all,

This is for merge two columns ,but if you want row wise plz put rowindex in columnindex place., This is working ., thanks to all

Using gridBrush As Brush = New SolidBrush(Color.Black), backColorBrush As Brush = New SolidBrush(e.CellStyle.BackColor)

                Using gridLinePen As Pen = New Pen(gridBrush)

                    ' Clear cell  

                    e.Graphics.FillRectangle(backColorBrush, e.CellBounds)

                    ' Draw line (bottom border and right border of current cell)  

                    'If next row cell has different content, only draw bottom border line of current cell  

                    e.Graphics.DrawLine(gridLinePen, e.CellBounds.Left, e.CellBounds.Bottom - 1, e.CellBounds.Right, e.CellBounds.Bottom - 1)

                    If e.ColumnIndex < gridPreFinal2.Columns.Count - 1 AndAlso gridPreFinal2.Columns(e.ColumnIndex + 1).HeaderText.ToString() <> gridPreFinal2.Columns(e.ColumnIndex).HeaderText.ToString() Then

                        e.Graphics.DrawLine(gridLinePen, e.CellBounds.Right - 1, e.CellBounds.Top, e.CellBounds.Right - 1, e.CellBounds.Bottom)

                    End If

                    ' Draw right border line of current cell  

                    'e.CellBounds.Right - 1, e.CellBounds.Top, e.CellBounds.Right - 1, e.CellBounds.Bottom)

                    'cURRENT_cELL_vALUE = gridPreFinal2.Columns(e.ColumnIndex).HeaderText

                    Dim recdest As RectangleF = RectangleF.Empty

                    Dim sf As New StringFormat

                    sf.Alignment = StringAlignment.Center

                    sf.LineAlignment = StringAlignment.Center

                    sf.Trimming = StringTrimming.EllipsisCharacter

                    'sf.

                    Dim WIDTH_S As Integer

                    WIDTH_S = 183 + 50

                    recdest = New RectangleF(e.CellBounds.Left - (WIDTH_S + WIDTH_S + WIDTH_S), e.CellBounds.Top, WIDTH_S + WIDTH_S, e.CellBounds.Height)

                    ' draw/fill content in current cell, and fill only one cell of multiple same cells  

                    If Not e.Value Is Nothing Then

                        If e.ColumnIndex = 0 Then

                            nulstring = e.Value.ToString

                            e.CellStyle.BackColor = Color.Orange

                            recdest = New RectangleF(e.CellBounds.Left, e.CellBounds.Top, 100, 40)

                            e.Graphics.DrawString(nulstring, e.CellStyle.Font, Brushes.White, recdest, sf)

                        Else

                            If e.RowIndex = -1 AndAlso gridPreFinal2.Columns(e.ColumnIndex - 1).HeaderText.ToString() = gridPreFinal2.Columns(e.ColumnIndex).HeaderText.ToString() Then

                            Else

                                nulstring = e.Value.ToString

                                e.CellStyle.BackColor = Color.Orange

                                recdest = New RectangleF(e.CellBounds.Left, e.CellBounds.Top, 100, 40)

                                e.Graphics.DrawString(nulstring, e.CellStyle.Font, Brushes.White, recdest, sf)

                            End If

                        End If

                    End If

                    e.Handled = True

                End Using

            End Using

Answer 10

Using gridBrush As Brush = New SolidBrush(Color.Black), backColorBrush As Brush = New SolidBrush(e.CellStyle.BackColor)

                Using gridLinePen As Pen = New Pen(gridBrush)

                    ' Clear cell  

                    e.Graphics.FillRectangle(backColorBrush, e.CellBounds)

                    ' Draw line (bottom border and right border of current cell)  

                    'If next row cell has different content, only draw bottom border line of current cell  

                    e.Graphics.DrawLine(gridLinePen, e.CellBounds.Left, e.CellBounds.Bottom - 1, e.CellBounds.Right, e.CellBounds.Bottom - 1)

                    If e.ColumnIndex < gridPreFinal2.Columns.Count - 1 AndAlso gridPreFinal2.Columns(e.ColumnIndex + 1).HeaderText.ToString() <> gridPreFinal2.Columns(e.ColumnIndex).HeaderText.ToString() Then

                        e.Graphics.DrawLine(gridLinePen, e.CellBounds.Right - 1, e.CellBounds.Top, e.CellBounds.Right - 1, e.CellBounds.Bottom)

                    End If

                    ' Draw right border line of current cell  

                    'e.CellBounds.Right - 1, e.CellBounds.Top, e.CellBounds.Right - 1, e.CellBounds.Bottom)

                    'cURRENT_cELL_vALUE = gridPreFinal2.Columns(e.ColumnIndex).HeaderText

                    Dim recdest As RectangleF = RectangleF.Empty

                    Dim sf As New StringFormat

                    sf.Alignment = StringAlignment.Center

                    sf.LineAlignment = StringAlignment.Center

                    sf.Trimming = StringTrimming.EllipsisCharacter

                    'sf.

                    Dim WIDTH_S As Integer

                    WIDTH_S = 183 + 50

                    recdest = New RectangleF(e.CellBounds.Left - (WIDTH_S + WIDTH_S + WIDTH_S), e.CellBounds.Top, WIDTH_S + WIDTH_S, e.CellBounds.Height)

                    ' draw/fill content in current cell, and fill only one cell of multiple same cells  

                    If Not e.Value Is Nothing Then

                        If e.ColumnIndex = 0 Then

                            nulstring = e.Value.ToString

                            e.CellStyle.BackColor = Color.Orange

                            recdest = New RectangleF(e.CellBounds.Left, e.CellBounds.Top, 100, 40)

                            e.Graphics.DrawString(nulstring, e.CellStyle.Font, Brushes.White, recdest, sf)

                        Else

                            If e.RowIndex = -1 AndAlso gridPreFinal2.Columns(e.ColumnIndex - 1).HeaderText.ToString() = gridPreFinal2.Columns(e.ColumnIndex).HeaderText.ToString() Then

                            Else

                                nulstring = e.Value.ToString

                                e.CellStyle.BackColor = Color.Orange

                                recdest = New RectangleF(e.CellBounds.Left, e.CellBounds.Top, 100, 40)

                                e.Graphics.DrawString(nulstring, e.CellStyle.Font, Brushes.White, recdest, sf)

                            End If

                        End If

                    End If

                    e.Handled = True

                End Using

            End Using

Thanks

Mathan

tamilNadu

Answer 11

The best solution will be:

                Using gridBrush As Brush = New SolidBrush(Me.DataGridView1.GridColor), backColorBrush As Brush = New SolidBrush(e.CellStyle.BackColor)

                    Using gridLinePen As Pen = New Pen(gridBrush)
                        ' Clear cell   
                        e.Graphics.FillRectangle(backColorBrush, e.CellBounds)

                        ' Draw line (bottom border and right border of current cell)   
                        'If next row cell has different content, only draw bottom border line of current cell   
                        If e.RowIndex < DataGridView1.Rows.Count - 1 AndAlso DataGridView1.Rows(e.RowIndex + 1).Cells(e.ColumnIndex).Value.ToString() <> e.Value.ToString() Then
                            e.Graphics.DrawLine(gridLinePen, e.CellBounds.Left, e.CellBounds.Bottom - 1, e.CellBounds.Right - 1, e.CellBounds.Bottom - 1)
                        End If

                        ' Draw right border line of current cell   
                        e.Graphics.DrawLine(gridLinePen, e.CellBounds.Right - 1, e.CellBounds.Top, e.CellBounds.Right - 1, e.CellBounds.Bottom)

                        ' draw/fill content in current cell, and fill only one cell of multiple same cells   
                        If Not e.Value Is Nothing Then
                            Dim previos As Integer = 0
                            Dim siguientes As Integer = 0
                            For i As Integer = e.RowIndex - 1 To 0 Step -1
                                If DataGridView1.Item(e.ColumnIndex, i).Value <> e.Value Or i = 0 Then
                                    previos = e.RowIndex - i - 1
                                    Exit For
                                End If
                            Next
                            For i As Integer = e.RowIndex + 1 To DataGridView1.Rows.Count - 1
                                If DataGridView1.Item(e.ColumnIndex, i).Value <> e.Value Or DataGridView1.Rows.Count - 1 = i Then
                                    siguientes = i - e.RowIndex - 1
                                    Exit For
                                End If
                            Next

                            If siguientes = previos Or siguientes - 1 = previos Then
                                e.Graphics.DrawString(CType(e.Value, String), e.CellStyle.Font, Brushes.Black, e.CellBounds.X + 2, e.CellBounds.Y + 3, StringFormat.GenericDefault)
                            End If
                            'End If
                        End If

                        e.Handled = True
                    End Using
                End Using

 

This puts the value near to the middle of the merged cells

Answer 12

your solution seems very good. now I want to use your code in a sub and call it. What I want to do is to transfer dgv, e, RowIndex (say 1 to 2) and  ColumnIndex (say 3 to 4) to call the sub. I don't know how to modify 

                  e.Graphics.FillRectangle(backColorBrush, e.CellBounds)

Thank you.

Answer 13

I use this code: 

    Private Sub DataGridView1_CellPainting(sender As Object, e As System.Windows.Forms.DataGridViewCellPaintingEventArgs) Handles DataGridView1.CellPainting
        If DataGridView1.Columns(e.ColumnIndex).Tag = "M" AndAlso e.RowIndex <> -1 Then
            Using gridBrush As Brush = New SolidBrush(Me.DataGridView1.GridColor), backColorBrush As Brush = New SolidBrush(e.CellStyle.BackColor)

                Using gridLinePen As Pen = New Pen(gridBrush)
                    ' Clear cell   
                    e.Graphics.FillRectangle(backColorBrush, e.CellBounds)

                    ' Draw line (bottom border and right border of current cell)   
                    'If next row cell has different content, only draw bottom border line of current cell   
                    If e.RowIndex = DataGridView1.Rows.Count - 1 OrElse DataGridView1.Item(e.ColumnIndex, e.RowIndex + 1).Value.ToString() <> e.Value.ToString() Then
                        e.Graphics.DrawLine(gridLinePen, e.CellBounds.Left, e.CellBounds.Bottom - 1, e.CellBounds.Right - 1, e.CellBounds.Bottom - 1)
                    End If

                    ' Draw right border line of current cell   
                    e.Graphics.DrawLine(gridLinePen, e.CellBounds.Right - 1, e.CellBounds.Top, e.CellBounds.Right - 1, e.CellBounds.Bottom)

                    ' draw/fill content in current cell, and fill only one cell of multiple same cells   
                    If Not e.Value Is Nothing Then
                        'If e.RowIndex > 0 AndAlso DataGridView1.Rows(e.RowIndex - 1).Cells(e.ColumnIndex).Value.ToString() = e.Value.ToString() Then
                        'Else


                        Dim previos As Integer = 0
                        Dim siguientes As Integer = 0
                        For i As Integer = e.RowIndex - 1 To 0 Step -1
                            If DataGridView1.Item(e.ColumnIndex, i).Value <> e.Value Or i = 0 Or DataGridView1.Item(e.ColumnIndex, i).Displayed = False Then
                                previos = e.RowIndex - i - 1
                                Exit For
                            End If
                        Next
                        For i As Integer = e.RowIndex + 1 To DataGridView1.Rows.Count - 1
                            If DataGridView1.Item(e.ColumnIndex, i).Value <> e.Value Or DataGridView1.Rows.Count - 1 = i Or DataGridView1.Item(e.ColumnIndex, i).Displayed = False Then
                                siguientes = i - e.RowIndex - 1
                                Exit For
                            End If
                        Next

                        If siguientes = previos Or siguientes - 1 = previos Then
                            'DataGridView1.Item(e.ColumnIndex, i - 1).Value = vbNullString
                            'DataGridView1.Item(Col, i).ContentBounds.Y = DataGridView1.Item(Col, i).ContentBounds.Y - 10
                            e.Graphics.DrawString(CType(e.Value, String), e.CellStyle.Font, Brushes.Black, e.CellBounds.X + 2, e.CellBounds.Y + 2, StringFormat.GenericDefault)
                        End If
                        'End If
                    End If

                    e.Handled = True
                End Using
            End Using
        End If
    End Sub

    Private Sub DataGridView1_Scroll(sender As Object, e As System.Windows.Forms.ScrollEventArgs) Handles DataGridView1.Scroll
        'TODO: don't refresh when there are no merged cells
        If e.Type = ScrollEventType.SmallDecrement Or e.Type = ScrollEventType.SmallIncrement Then
            If Not (DataGridView1.FirstDisplayedCell.RowIndex + DataGridView1.DisplayedRowCount(True) = DataGridView1.Rows.Count) Then
                DataGridView1.Refresh()
            End If
        End If
    End Sub

In the "Tag" property set if you want merge and do DataGridView1.Refresh() to redraw once you set which columns you want to merge

Answer 14

Greetings All,

I used the great ideas from the other postings to learn more about the "beast" that is the DataGridView.  I arrived at a fairly simple solution that does what I was looking for with minimal intrution in the event process:

    Private Sub dgvDMS_CellPainting(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellPaintingEventArgs) Handles dgvDMS.CellPainting

        If e.ColumnIndex <> 0 Then Exit Sub

        'Only the Serial Number column

        'Is the value of the next row the same
        If e.RowIndex + 1 < dgvDMS.Rows.Count Then
            If e.Value = dgvDMS.Rows(e.RowIndex + 1).Cells(e.ColumnIndex).Value Then
                e.AdvancedBorderStyle.Bottom = DataGridViewAdvancedCellBorderStyle.None
            End If
        End If

        'Is the previous column cell value the same
        If e.RowIndex >= 1 Then
            If e.Value = dgvDMS.Rows(e.RowIndex - 1).Cells(e.ColumnIndex).Value Then
                e.Graphics.FillRectangle(New SolidBrush(e.CellStyle.BackColor), e.CellBounds)
                e.PaintBackground(e.CellBounds, False)
                e.Handled = True
            End If
        End If

    End Sub

Answer 15

...or...

1.- Set the "CellBorderStyle" to "None"

• Select the DataGridView object with your cursor
• Find the "CellBorderStyle" property on the Properties window
• Change its value to "None"

2.- Create additional thin columns and rows between your current regular columns and rows.  A thickness of 2 will do and is also the minimum allowed.  Make sure you set the "MinimumWidth" property of each column to "2" before setting the "Width" property to "2".

• Select the DataGridView object with your cursor and click on the tiny arrow on the upper-right corner
• Select "Edit Columns" from the menu
• Use intituive common-sense to add thin columns in between each regular column, based on the instructions above
• ...or... add thin columns and rows programatically

3.- Manipulate the color of the cells in these extra thin columns and rows to create the illusion of grid-lines.  Use the same color as your other cells to create the illusion of merged cells.

I used this method to avoid the painful and complicated "DrawLine" method.  Of course, if you copy-paste data from the DataGridView control to excel, the extra columns and rows will also be copied and pasted.  But if you only need it for aestetics as I did, that will not be an issue.