//--- S A M P L E : 
// -- UpdateDropList(document.myform.main_id, document.myform.sub_id,'<?=$sub_selected_id?>',SubNames,SubIDs);

function ClearDropList(OptionList) {
    OptionList.length = 1;
}

function LoadDropList(Index,sub_select, selected_value,NameArray,ValueArray) {
	if (Index > 0){	
	        var CurrentName = NameArray[Index - 1].split('||');
		var CurrentValue = ValueArray[Index - 1].split('||');
		for (var i=0; i<CurrentName.length; i++){
		  sub_select.options[i+1] = new Option(CurrentName[i], CurrentValue[i], false, false);
		  if(CurrentValue[i] == selected_value) {  sub_select.options[i+1].selected = true;  }
		}
	}
}

function UpdateDropList(main_select, sub_select,selected_value,NameArray,ValueArray) {
	var CurrSub = sub_select.selectedIndex;
	ClearDropList(sub_select);
	LoadDropList(main_select.selectedIndex, sub_select,selected_value,NameArray,ValueArray);
	
	var val = main_select.options[main_select.selectedIndex].value;
	if (val != "") {
		sub_select.disabled = false;
	} else {
		sub_select.disabled = true;
	}
}

//-----------  E N D   D R O P   L I S T   F U N C T I O N  ----------