//返回文件大小	public function formatsize($size)	{		$arr 	= array('Byte', 'KB', 'MB', 'GB', 'TB', 'PB');		$e 		= floor(log($size)/log(1024));		return number_format(($size/pow(1024,floor($e))),2,'.','').' '.$arr[$e];	}