您可以用一个函数找到以秒为单位的执行时间。

// ampersand is important thing here
function microSec( & $ms ) {
    if (\floatval( $ms ) == 0) {
        $ms = microtime( true );
    }
    else {
        $originalMs = $ms;
        $ms = 0;
        return microtime( true ) - $originalMs;
    }
}

// you don't have to define $ms variable. just function needs
// it to calculate the difference.
microSec($ms);
sleep(10);
echo microSec($ms) . " seconds"; // 10 seconds

for( $i = 0; $i < 10; $i++) {
    // you can use same variable everytime without assign a value
    microSec($ms);
    sleep(1);
    echo microSec($ms) . " seconds"; // 1 second
}

for( $i = 0; $i < 10; $i++) {
    // also you can use temp or useless variables
    microSec($xyzabc);
    sleep(1);
    echo microSec($xyzabc) . " seconds"; // 1 second
}

$start = microtime(true);
for ($i = 0; $i < 10000; ++$i) {
    // do something
}
$total = microtime(true) - $start;
echo $total;

看()。

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”

这样会更清楚

<?php

$start = hrtime(true);

while (...) {
}

$duration = hrtime(true) - $start;
echo  $duration * 1000 ." -> microseconds". PHP_EOL; 
echo  $duration * 1000000 ." -> milliseconds". PHP_EOL; 
echo  $duration * 1e6 ." -> milliseconds". PHP_EOL; 

结果

37180000 -> microseconds
37180000000 -> milliseconds
37180000000 -> milliseconds

<?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