PHP deletes a directory and all subordinate directories and file codes within the directory

//PHP删除目录和目录内所有的下级目录、文件代码
 function delDir( $dirName='' ){ 
     if ( $handle = opendir( "$dirName" ) ) {  
        while ( false !== ( $item = readdir( $handle ) ) ) {  
            if ( $item != "." && $item != ".." ) {  
                if ( is_dir( "$dirName/$item" ) ) {  
                     $this->delDir( "$dirName/$item" );
                } else {  
                        unlink( "$dirName/$item" );
                }  
            }  
        }  
        closedir( $handle );  
     }  
 }
   
 delDir('目录');