前端validate验证自定义remote

remote   : {
url : 'index.php?act=supplier&op=check_supplier_num',
type: 'get',
data:{
supplier_num : function(){
return $('#supplier_num').val();
}
}
}

public function check_supplier_numOp()
{
$result = model()->table('supplier')->where(array('supplier_num'=>$_GET['supplier_num']))->count();
if(intval($result)){
echo 'false';
}else{
echo 'true';
}
}