给model模型传数组参数

 $res = $this->Company->companyDischarge($this->user_id,array(0=>'c.limit_sum>0',1=>'cp.kh_city="'.$kh_city.'"'),$page,$this->num);

$conditions = array('c.limit_sum>0');
if(isset($_REQUEST['kh_city'])&&$_REQUEST['kh_city']){
    $conditions[] = 'kh_city="'.$_REQUEST['kh_city'].'"';
 }