Numbering row header in datagrid using C#

Question

Hello all i am using datagrid and it doesnot have auto numbering. so i used the following method to number in rowheader but the problem is the numbers are repeating and when they sort a column they are rearranging themselves..Also when i scroll the page, when the row goes out of visibility and when u scroll back again its number is changing..for example on page load you see 1 to 30 in order when u scroll up and down twice, the order can become 1,30,25,4,...etc..theres no specific order..it displays random number in row header.. please suggest a way out for me

In XAML page i called the method in the following way LoadingRow="dg_expSummary_LoadingRow"

In the backend the code is as follows

private void dg_expSummary_LoadingRow(object sender, DataGridRowEventArgs e)
{
   e.Row.Header = e.Row.GetIndex() + 1;
}

Answer 1

Try setting your column names once, at the right time. E.g. after setting the data source.

Answer 2

I'm doing this in VB.Net. Store the original result set row number in Row(x).Column(0).Tag and then:

Private Sub gridData_RowPostPaint(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewRowPostPaintEventArgs) Handles gridData.RowPostPaint

    Dim style As DataGridViewCellStyle
    Dim Pen As Pen
    Dim rec As RectangleF
    Dim format As StringFormat
    'Dim n As Integer

    'get style to use for row header cells            
    style = gridData.RowHeadersDefaultCellStyle

    'get pen (needed to get text brush)            
    Pen = New Pen(style.ForeColor)

    'get row rectangle and adjust to width of row header            
    rec = e.RowBounds
    rec.Width = gridData.RowHeadersWidth

    'create formating object to center row number            
    format = StringFormat.GenericTypographic
    Format.Alignment = StringAlignment.Center
        Format.LineAlignment = StringAlignment.Center

        'draw the row number in row header            
        e.Graphics.DrawString(gridData.Rows.Item(e.RowIndex).Cells(0).Tag.ToString(), style.Font, Pen.Brush, rec, format)

    End Sub

My code is adapted from a c# example found here: http://www.daniweb.com/forums/thread302079.html