function select_deselectAll (chkVal, idVal) 
{ 
    var frm = document.forms[0];
    // Loop through all elements
    for (i=0; i<frm.length; i++) 
    {
        // Look for our Header Template's Checkbox
        if (idVal.indexOf ('CheckAll') != -1) 
        {
            // Check if main checkbox is checked, then select or deselect datagrid checkboxes 
            if(chkVal == true) 
            {
                frm.elements[i].checked = !frm.elements[i].disabled;
            } 
            else 
            {
                frm.elements[i].checked = false;
            }
            // Work here with the Item Template's multiple checkboxes
        } 
        else if (idVal.indexOf ('DeleteCheckBox') != -1) 
        {
            // Check if any of the checkboxes are not checked, and then uncheck top select all checkbox
            if(frm.elements[i].checked == false) 
            {
                frm.elements[1].checked = false; //Uncheck main select all checkbox
            }
        }
    }
}

/*
	For making an HTML Element visible or hidden by means of the display attribute on its CSS style.
	Typically 'id' should be a div. 
*/
function makeElementVisible(id) 
{
	var element = document.getElementById(id);
	if (element.style.visibility != "visible")
	{
		element.style.visibility = "visible";
		element.style.display = "block"; 	
		element.style.height = "auto";
	}
	else
	{
		element.style.visibility = "hidden";
		element.style.height = "0px";
		if (window.navigator.appName.toLowerCase().indexOf("microsoft") > -1)
		{
			element.style.display = "none"; 	
		}	
	}	
}