计算页面执行时间

以下类定义了一个计时器,将你的执行脚本加入到"容器"内即可(请看注释)
<? class timer{ var $StartTime = 0;var $StopTime = 0;var $TimeSpent = 0;function start(){$this->StartTime = microtime();} function stop(){ $this->StopTime　= microtime();} function spent(){   if ($this->TimeSpent) {   return $this->TimeSpent;     } else {$StartMicro = substr($this->StartTime,0,10);$StartSecond = substr($this->StartTime,11,10);$StopMicro　 = substr($this->StopTime,0,10);$StopSecond　= substr($this->StopTime,11,10);$start = doubleval($StartMicro) + $StartSecond;$stop　= doubleval($StopMicro) + $StopSecond;$this->TimeSpent = $stop - $start;return substr($this->TimeSpent,0,8)."秒";        }     }// end function spent();}//end class timer;//例子  $timer = new timer;    $timer->start();/*你的代码放在此处*/$timer->stop();echo "执行本SCRIPT共".$timer->spent();?>