HRTime擴展實現了高分辨率的StopWatch類。它在不同平臺上使用了最好的API，從而使解析度達到了納秒級。它還可以使用底層API傳遞的低級滴答來實現自定義秒表。 從PHP 7.3.0開始，相關函數[hrtime（）](https://www.php.net/manual/en/function.hrtime.php)是核心部分。 [https://pecl.php.net/package/hrtime](https://pecl.php.net/package/hrtime) * [范例](https://www.php.net/manual/zh/hrtime.examples.php) * [Basic usage](https://www.php.net/manual/zh/hrtime.example.basic.php) * [HRTime\\PerformanceCounter](https://www.php.net/manual/zh/class.hrtime-performancecounter.php)— The HRTime\\PerformanceCounter 類 * [HRTime\\PerformanceCounter::getFrequency](https://www.php.net/manual/zh/hrtime-performancecounter.getfrequency.php)— 計時器頻率(以秒為單位) * [HRTime\\PerformanceCounter::getTicks](https://www.php.net/manual/zh/hrtime-performancecounter.getticks.php)— 當前從系統滴答 * [HRTime\\PerformanceCounter::getTicksSince](https://www.php.net/manual/zh/hrtime-performancecounter.gettickssince.php)— 從給定值開始計時 ***** * [HRTime\\StopWatch](https://www.php.net/manual/zh/class.hrtime-stopwatch.php)— The HRTime\\StopWatch 類 * [HRTime\\StopWatch::getElapsedTicks](https://www.php.net/manual/zh/hrtime-stopwatch.getelapsedticks.php)—獲取所有間隔的運行時間 * [HRTime\\StopWatch::getElapsedTime](https://www.php.net/manual/zh/hrtime-stopwatch.getelapsedtime.php)—取所有間隔的運行時間 * [HRTime\\StopWatch::getLastElapsedTicks](https://www.php.net/manual/zh/hrtime-stopwatch.getlastelapsedticks.php)— 獲取最后一個間隔的運行時間 * [HRTime\\StopWatch::getLastElapsedTime](https://www.php.net/manual/zh/hrtime-stopwatch.getlastelapsedtime.php)— 獲取最后一個間隔的運行時間 * [HRTime\\StopWatch::isRunning](https://www.php.net/manual/zh/hrtime-stopwatch.isrunning.php)— 測量是否正在運行 * [HRTime\\StopWatch::start](https://www.php.net/manual/zh/hrtime--開始時間測量 * [HRTime\\StopWatch::stop](https://www.php.net/manual/zh/hrtime-停止時間測量 ***** * [HRTime\\Unit](https://www.php.net/manual/zh/class.hrtime-unit.php)— The HRTime\Unit 類