php计算脚本之行时间

通过记录开始时间和结束时间计算一段脚本的之行时间

<?php 
//Create a variable for start time 
$time_start = microtime(true); 
// Place your PHP/HTML/JavaScript/CSS/Etc. Here 
//Create a variable for end time 
$time_end = microtime(true); 
//Subtract the two times to get seconds 
$time = $time_end - $time_start; 
echo 'Script took '.$time.' seconds to exicute'; 
?>