利用 localStorage 实现页面刷新后倒计时不重置

核心代码实现

<!doctype html>
<html>

  <head>
    <meta charset="utf-8">
    <title>简单易用的倒计时js代码</title>

  </head>

  <body>
    <div id="time"></div>
    <script src="js/jquery-git.js"></script>
    <script>
      localStorage.setItem('start', new Date().getTime());
      countDown(localStorage.getItem('start'));

      function countDown(startTime) {
        var time = setInterval(function() {
          var currentTime = new Date();
          var second = 59 - parseInt(((currentTime.getTime() - startTime) / 1000) % 60);
          var min = 4 - parseInt((currentTime.getTime() - startTime) / 60000);

          if(min < 10) {
            min = "0" + min;
          }
          if(second < 10) {
            second = "0" + second;
          }

          var countDown = min + ":" + second;
          $('#time').html(countDown);

          if(second == 0 && min == 0) {
            clearInterval(time);
          }
        }, 1000)
      }
    </script>

  </body>

</html>