你可以通过以下方式使用微时间(true):

把这个放在你的php文件的开头:

//place this before any script you want to calculate time
$time_start = microtime(true);

//你的脚本代码在这里

// do something

把这个放在你的php文件的末尾:

// Display Script End time
$time_end = microtime(true);

//dividing with 60 will give the execution time in minutes other wise seconds
$execution_time = ($time_end - $time_start)/60;

//execution time of the script
echo '<b>Total Execution Time:</b> '.$execution_time.' Mins';

它将在几分钟内输出结果。

<?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

我的方法是使用hrtime，它是为性能指标而创建的，它独立于系统时间。Hrtime不受系统时间变化的影响。hrtime自PHP 7.3.0起可用

$start = hrtime(true);
sleep(5); // do something, in your case a loop
$end = hrtime(true);
$eta = $end - $start;
// convert nanoseconds to milliseconds
$eta /= 1e+6;
echo "Code block was running for $eta milliseconds";

输出:

代码块运行了5000.495206毫秒

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”

如果你想以秒为单位显示时间:

<?php

class debugTimer
{
    private $startTime;
    private $callsCounter;

    function __construct()
    {
        $this->startTime = microtime(true);
        $this->callsCounter = 0;
    }

    public function getTimer(): float
    {
        $timeEnd = microtime(true);
        $time = $timeEnd - $this->startTime;
        $this->callsCounter++;
        return $time;
    }

    public function getCallsNumber(): int
    {
        return $this->callsCounter;
    }
}

$timer = new debugTimer();
usleep(100);
echo '<br />\n
    ' . $timer->getTimer() . ' seconds before call #' . $timer->getCallsNumber();

usleep(100);
echo '<br />\n
    ' . $timer->getTimer() . ' seconds before call #' . $timer->getCallsNumber();

您的想法是正确的，不过microtime()函数可以提供更精确的计时。

如果循环内的内容是快速的，则可能的表观消耗时间将为零。如果是这样，则围绕该代码封装另一个循环并重复调用它。请确保将差值除以迭代次数，以得到每一次的时间。我已经分析了需要10,000,000次迭代才能获得一致、可靠的计时结果的代码。