三级联动php+ajax+mysql

php:


 where('ParentId=1')->select();
    	$this->assign('area',$area);
        $this->display();
    }
    
    public function getCity(){
    	$ParentId=I('post.ParentId');
    	$current_city=M('citys')->where('ParentId='.$ParentId)->select();
    	$data['data']=$current_city;
    	$this->ajaxReturn($data);
    }
    
    public function getCounty(){
    	$ParentId=I('post.ParentId');
    	$current_county=M('citys')->where('ParentId='.$ParentId)->select();
    	$data['data']=$current_county;
    	$this->ajaxReturn($data);
    }
}

html:




 







 
	
  
三级联动
	
   请选择  {$vo['shortname']}  
	
   请选择 
	
   请选择