DataGridView控件中如何自动产生行号

Imports System.Text
Imports System.Windows.Forms
Imports System.Drawing
Public Class Form1

Private Sub DataGridView1_RowPostPaint(sender As Object, e As System.Windows.Forms.DataGridViewRowPostPaintEventArgs) Handles DataGridView1.RowPostPaint
        Dim mFont As New System.Drawing.Font("Cambria", 9, FontStyle.Italic) '设置字体字号
        Dim rowIdx As Long = (e.RowIndex + 1).ToString()
        Dim centerFormat As New StringFormat()
        Dim Alignment = StringAlignment.Center
        Dim LineAlignment = StringAlignment.Center
        Dim headerBounds As New Rectangle(e.RowBounds.Left + 10, e.RowBounds.Top + 5, DataGridView1.RowHeadersWidth, e.RowBounds.Height)
        e.Graphics.DrawString(rowIdx, mFont, SystemBrushes.ControlText, headerBounds, centerFormat)

    End Sub
End Class