if (e.Item is GridDataItem)
GridDataItem item = (GridDataItem)e.Item;
CheckBox chkbx = (CheckBox)item["ClientSelectColumn"].Controls;
"OnClick", "return alert('" + chkbx.Checked + "');");
But every time, the value is displayed as false after I check the box. I just want to get the value of the checkbox after it is selected.