PHP检验代码执行效率—时间统计方法

<?php
class runtime
{
        var$StartTime=;
        var$StopTime=;
        function get_microtime()
        {
                list($usec,$sec) =explode('',microtime());
                return ((float)$usec+(float)$sec);
        }

        function start()
        {
                $this->StartTime =$this->get_microtime();
        }

        function stop()
        {
                $this->StopTime =$this->get_microtime();
        }

        function spent()
        {
                returnround(($this->StopTime -$this->StartTime) *,);
        }
}

//实例开始$runtime=new runtime;
$runtime->start();

//Start

//Here is your code

//End$runtime->stop();
echo"执行时间: ".$runtime->spent()." 毫秒";
?>