thinkphp一键清除缓存的方法

后台控制器：
namespace Home\Controller;
use Think\Controller;
class HuancuController extends Controller{
                private function _deleteDir($R){
                $handle = opendir($R);
                while(($item = readdir($handle)) !== false){
                if($item != '.' and $item != '..'){
                if(is_dir($R.'/'.$item)){
                $this->_deleteDir($R.'/'.$item);
                }else{
                if(!unlink($R.'/'.$item))
                die('error!');
                }
                }
                }
                closedir( $handle );
                return rmdir($R);
                }
                public function clearRuntime(){
                if($_POST['user']==1){
                        if($this->_deleteDir("./Runtime/")){
                            $this->ajaxReturn(1);
                        }
                }
                }
        
}

前台代码 ajax请求：