function isnull(str)
{if(str==null||str=="")return true;
 return false;
}
var obj1;
var obj2;
var cityStep=1;
function initCity(step){ 
	cityStep=step;
}
function initProvince(){
	obj1=document.getElementById("province");
	obj2=document.getElementById("city");
	for(var i=0;i<pc.length;i++)	{
			oOption = document.createElement("OPTION");
			oOption.value=i+'|'+pc[i][0];
			oOption.text=pc[i][0];
			obj1.options.add(oOption);			
	}
}
function setProvinceById(pid,cid)
{
	if(isnull(pid)) pid='-1';
	if(isnull(cid)) cid='-1';
	initProvince();
	if(pid>=0){
			obj1.selectedIndex=parseInt(pid)+cityStep;
			setCityById(parseInt(pid),parseInt(cid));
		}
}
function setCityById(pid,cid){
	if(pid>=0){
		for(var i=1;i<pc[pid].length-1;i++){
			  oOption = document.createElement("OPTION");
				oOption.value=i+'|'+pc[pid][i];
				oOption.text=pc[pid][i];
				obj2.options.add(oOption);				
		}
		if(cid>=0)
			obj2.selectedIndex=cid;
	}
else
	obj2.selectedIndex=0;
}
function getCity()
{
	clearObj(obj2);
	var pid=obj1.selectedIndex-1;
	setCityById(pid,0)
	
}
function clearObj(ObjId)
{
	try{
  var i;
  if(ObjId.length<1) return;
  for(i=ObjId.length-1;i>=0+cityStep;i--)
			ObjId.remove(i);
		}catch(ex){}
}