dirname性能

页面运行时间: 0.089148044586182 秒

页面运行时间: 0.0088009834289551 秒

10w次运行的结果

<?php

$pagestartime = microtime();
for ($index = 0; $index < 100000; $index++) {
    dirname(__FILE__);
}
$pageendtime = microtime();
$starttime = explode(" ", $pagestartime);
$endtime = explode(" ", $pageendtime);
$totaltime = $endtime[0] - $starttime[0] + $endtime[1] - $starttime[1];
$timecost = sprintf("%s", $totaltime);
echo "页面运行时间: $timecost 秒<br>";

$pagestartime = microtime();
for ($index = 0; $index < 100000; $index++) {
    
}
$pageendtime = microtime();
$starttime = explode(" ", $pagestartime);
$endtime = explode(" ", $pageendtime);
$totaltime = $endtime[0] - $starttime[0] + $endtime[1] - $starttime[1];
$timecost = sprintf("%s", $totaltime);
echo "页面运行时间: $timecost 秒";
?>