Display header in GridView cell when mouse pointer hovers over it

protected void GridView1_RowDataBound(object sender, System.Web.UI.WebControls.GridViewRowEventArgs e)
{
 if ((e.Row.RowType == DataControlRowType.DataRow) | (e.Row.RowType == DataControlRowType.Header)) {
  foreach (DataControlFieldCell GridViewDataControlFieldCell in e.Row.Cells) {
   //Remove any hidden hyphens that might be in the header.
   string GridViewHeaderText = GridViewDataControlFieldCell.ContainingField.HeaderText.Replace(Strings.Chr(173), "");
   if (e.Row.RowType == DataControlRowType.DataRow) {
    GridViewDataControlFieldCell.Attributes.Add("Title", GridViewHeaderText);
    GridViewDataControlFieldCell.Attributes.Add("onmouseover", "this.bgColor='lightyellow'");
    GridViewDataControlFieldCell.Attributes.Add("onmouseout", "this.bgColor=''");
   } else {
    GridViewDataControlFieldCell.Attributes.Add("Title", "Click link to sort by " + GridViewHeaderText);
   }
  }
 }
}