ItemDataBound事件如何无效

ItemDataBound事件怎么无效?
private   void   DataGrid1_ItemDataBound(object   sender,   System.Web.UI.WebControls.DataGridItemEventArgs   e)
{
      if(e.Item.DataSetIndex   !=   -1)
      {
int   len=e.Item.Cells[1].Text.Length;
if(len> 6)
{
      e.Item.Cells[1].Text=e.Item.Cells[1].Text.Substring(0,6)+ "... ";
}
      }
}

想达到截断字符串长度的目的,但好像没有被执行;事件丢失?该怎么办?

------解决方案--------------------------------------------------------
<asp:DataGrid ID =grid runat=server OnItemDataBound= "grid_ItemDataBound " > </asp:DataGrid>
------解决方案--------------------------------------------------------
楼上解了