function SelectAll(CheckBoxControl, GridName) {
    var cb = document.getElementById(CheckBoxControl);
    var i;
    for (i = 0; i < document.forms[0].elements.length; i++) {
        if ((document.forms[0].elements[i].type == 'checkbox') && (document.forms[0].elements[i].name.indexOf(GridName) > -1)) {
            if (cb.checked == true)
                document.forms[0].elements[i].checked = true;
            else
                document.forms[0].elements[i].checked = false;


        }
    }
}