创建文件loadtime.php

<?php
class loadTime{
    private $time_start     =   0;
    private $time_end       =   0;
    private $time           =   0;
    public function __construct(){
        $this->time_start= microtime(true);
    }
    public function __destruct(){
        $this->time_end = microtime(true);
        $this->time = $this->time_end - $this->time_start;
        echo "Loaded in $this->time seconds\n";
    }
}

而不是在<?PHP: loadtime.php美元loadtime = new loadtime ();

当页面加载结束时，会写“加载在x秒内”

<?php
// Randomize sleeping time
usleep(mt_rand(100, 10000));

// REQUEST_TIME_FLOAT is available in the $_SERVER superglobal array.
// It contains the timestamp of the start of the request with microsecond precision.
$time = microtime(true) - $_SERVER["REQUEST_TIME_FLOAT"];

echo "Did nothing in $time seconds\n";
?>

这是这个的链接

下面是一个返回小数秒的实现(即1.321秒)

/**
 * MICROSECOND STOPWATCH FOR PHP
 *
 * Class FnxStopwatch
 */
class FnxStopwatch
{
    /** @var float */
    private $start,
            $stop;

    public function start()
    {
        $this->start = self::microtime_float();
    }
    public function stop()
    {
        $this->stop = self::microtime_float();
    }
    public function getIntervalSeconds() : float
    {
        // NOT STARTED
        if (empty($this->start))
            return 0;
        // NOT STOPPED
        if (empty($this->stop))
            return ($this->stop - self::microtime_float());

        return $interval = $this->stop - $this->start;
    }

    /**
     * FOR MORE INFO SEE http://us.php.net/microtime
     *
     * @return float
     */
    private static function microtime_float() : float
    {
        list($usec, $sec) = explode(" ", microtime());

        return ((float)$usec + (float)$sec);
    }
}

这里有一个函数，可以计时PHP代码的任何部分的执行，很像Python的timeit模块:https://gist.github.com/flaviovs/35aab0e85852e548a60a

如何使用:

include('timeit.php');
const SOME_CODE = '
        strlen("foo bar");
';
$t = timeit(SOME_CODE);
print "$t[0] loops; $t[2] per loop\n";

结果:

$ php x.php 
100000 loops; 18.08us per loop

免责声明:我是本文主旨的作者

EDIT: timeit现在是https://github.com/flaviovs/timeit上一个独立的、独立的项目

您可以使用$_SERVER超全局数组中的REQUEST_TIME。从文档中可以看到:

REQUEST_TIME 请求开始的时间戳。(自PHP 5.1.0起可用。) REQUEST_TIME_FLOAT 请求开始的时间戳，具有微秒精度。(自PHP 5.4.0起可用。)

这样就不需要在脚本的开头保存时间戳。你可以简单地做:

<?php
// Do stuff
usleep(mt_rand(100, 10000));

// At the end of your script
$time = microtime(true) - $_SERVER["REQUEST_TIME_FLOAT"];

echo "Did stuff in $time seconds\n";
?>

在这里，$time将包含自脚本开始以来所经过的时间，以秒为单位，具有微秒精度(例如。1.341为1秒和341微秒)

更多信息:

PHP文档:$_SERVER变量和microtime函数

下面是我用来测量平均时间的脚本

<?php

$times = [];
$nbrOfLoops = 4;
for ($i = 0; $i < $nbrOfLoops; ++$i) {
    $start = microtime(true);
    sleep(1);
    $times[] = microtime(true) - $start;
}

echo 'Average: ' . (array_sum($times) / count($times)) . 'seconds';