PHP 記錄頁面停留時間

首先在要監控的頁面添加JS如下

<script>var dt1 = new Date();window.onbeforeunload = function(){    var dt2 = new Date();    var ms = dt2.getTime() - dt1.getTime();    var img = new Image();    img.src = 'log.php?stay_ms=' + ms;}</script>

log.php 代碼如下

<?php$refer = '';if (isset($_SERVER['HTTP_REFERER'])){    $refer = $_SERVER['HTTP_REFERER'];}$user_agent = '';if (isset($_SERVER['HTTP_USER_AGENT'])){    $user_agent = $_SERVER['HTTP_USER_AGENT'];}$ip = $_SERVER['REMOTE_ADDR'];if (isset($_GET['stay_ms'])){    $log = '[' . date("Y-m-d H:i:s") . '] ' . $ip . ' ' . $refer . ' @ ' . number_format($_GET['stay_ms']) . "ms\r\n";    file_put_contents("log/log_" . date("Y-m-d") . ".txt", $log, FILE_APPEND);}if ($_SERVER['QUERY_STRING'] == '' || isset($_GET['day'])){    $day = isset($_GET['day']) ? $_GET['day'] : date("Y-m-d");    $file = "log/log_" .$day . ".txt";    if (file_exists($file))    {        $log = file_get_contents($file);        echo nl2br($log);    }}