Limit entry of only digits in a DataGridView column

use this event of datagrid for keypress...

private void grd_bill_master_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e)
    {
        try
        {
            e.Control.KeyPress +=
  new KeyPressEventHandler(Control_KeyPress);

     
    }

// and this will allowed values like Ex. 10.20 etc...

private void Control_KeyPress(object sender, KeyPressEventArgs e)
    {
       
        if (!char.IsControl(e.KeyChar)
 && !char.IsDigit(e.KeyChar)
 && e.KeyChar != '.')
        {
            e.Handled = true;
        }

        // only allow one decimal point
        if (e.KeyChar == '.'
            && (sender as TextBox).Text.IndexOf('.') > -1)
        {
            e.Handled = true;
        }
    }

Refer this hope it helps
http://msdn.microsoft.com/en-us/library/system.windows.forms.datagridview.cellvalidating.aspx[^]

For Windows Application You can validate value on keypress event
below is the Example.

Private Sub txt_amt_KeyPress(ByVal sender As System.Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles txt_amt.KeyPress
       Dim allowedChars As String = "0123456789." & vbBack & "\"
       If allowedChars.IndexOf(e.KeyChar) = -1 Then
           e.Handled = True
       End If
   End Sub

Private Sub dgvItemService_EditingControlShowing(sender As Object, e As DataGridViewEditingControlShowingEventArgs) Handles dgvItemService.EditingControlShowing
        If TypeOf e.Control Is TextBox Then
            Dim tb As TextBox = TryCast(e.Control, TextBox)
            
            'Remove Event handler keyPress early add if any
            RemoveHandler tb.KeyPress, AddressOf tb_KeyPress

            '3=Vol, 5=UPrice, 6=Discount are the desired columns
            If Me.dgvItemService.CurrentCell.ColumnIndex = 3 _
                Or Me.dgvItemService.CurrentCell.ColumnIndex = 5 _
                Or Me.dgvItemService.CurrentCell.ColumnIndex = 6 Then 

                AddHandler tb.KeyPress, AddressOf tb_KeyPress
            End If
        End If
    End Sub

    Private Sub tb_KeyPress(sender As Object, e As KeyPressEventArgs)
        If Not Char.IsControl(e.KeyChar) _
            And Not Char.IsDigit(e.KeyChar) _
            And e.KeyChar <> "." Then
            e.Handled = True
        End If
    End Sub

http://www.c-sharpcorner.com/Blogs/3301/validate-and-focus-datagridview-cell.aspx[^]


dataproperty of that column should numeric.

Hi Friend You Can use Ajax FilterTextBoxExtender for enter only numeric values in textbox 

<cc1:filteredtextboxextender id="FilteredTextBoxExtender2"  runat="server" targetcontrolid="txtAmount" filtermode="ValidChars" filtertype="Custom" validchars="0123456789." xmlns:cc1="#unknown">

OR You can use Regular Expression for validate.
See This Link.

http://www.devcurry.com/2010/03/using-regular-expression-to-validate.html[^]

1) Add an event of EditingControlShowing.
2) In EditingControlShowing, check that if the current cell lies in the desired column.
3) Register a new event of KeyPress in EditingControlShowing(if above condition is true).
4) Remove any KeyPress event added previously in EditingControlShowing.
5) In KeyPress event, check that if key is not digit then cancel the input.

Example:

private void dataGridView1_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e)
        {
            e.Control.KeyPress -= new KeyPressEventHandler(Column1_KeyPress);
            if (dataGridView1.CurrentCell.ColumnIndex == 0) //Desired Column
            {
                TextBox tb = e.Control as TextBox;
                if (tb != null)
                {
                    tb.KeyPress += new KeyPressEventHandler(Column1_KeyPress);
                }
            }
        }

private void Column1_KeyPress(object sender, KeyPressEventArgs e)
        {
            if (!char.IsControl(e.KeyChar)
                && !char.IsDigit(e.KeyChar))
            {
                e.Handled = true;
            }
        }

((DataGridViewTextBoxColumn)dataGridView1.Columns[1]).MaxInputLength = 59;