datagrid 页眉合并

http://www.codeproject.com/aspnet/MergeDatagridHeader.asp

private void DataGrid1_ItemDataBound(object sender, DataGridItemEventArgs e)
{
//产生序号，合并单元格
if(e.Item.ItemIndex!=-1)
{
e.Item.Cells[1].Text=Convert.ToString(e.Item.ItemIndex+1);//
}
else
{
e.Item.Cells[0].ColumnSpan=2;
e.Item.Cells[1].Visible=false;
}

}