A brief discussion on two ways to achieve countdown effects in JS (code examples)-JS Tutorial-php.cn

A brief discussion on two ways to achieve countdown effects in JS (code examples)

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Release： 2021-05-31 16:00:16

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This article mainly introduces the code examples of the two implementation methods of JS countdown. The article introduces it in great detail through the example code. It has certain reference learning value for everyone's study or work. Friends in need can refer to the recent browser development The interface countdown can be implemented using js. There are two ways:

A brief discussion on two ways to achieve countdown effects in JS (code examples)

One: Set the duration and countdown. For example, exam time, etc.

The code is as follows:

<html>
<head>
<meta charset="UTF-8">
<title>简单时长倒计时</title>
<SCRIPT type="text/javascript">
      var maxtime = 60 * 60; //一个小时，按秒计算，自己调整!
      function CountDown() {
        if (maxtime >= 0) {
          minutes = Math.floor(maxtime / 60);
          seconds = Math.floor(maxtime % 60);
          msg = "距离结束还有" + minutes + "分" + seconds + "秒";
          document.all["timer"].innerHTML = msg;
          if (maxtime == 5 * 60)alert("还剩5分钟");
            --maxtime;
        } else{
          clearInterval(timer);
          alert("时间到，结束!");
        }
      }
      timer = setInterval("CountDown()", 1000);
    </SCRIPT>
</head>
<body>
<p id="timer" style="color:red"></p>
<p id="warring" style="color:red"></p>
</body>
</html>

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A brief discussion on two ways to achieve countdown effects in JS (code examples)

2: Settings Timestamp for countdown. For example, the time until the end of the event, etc.

The code is as follows:

<html>
<head>
  <meta charset="UTF-8">
  <title>js简单时分秒倒计时</title>
  <script type="text/javascript">
    function countTime() {
      //获取当前时间
      var date = new Date();
      var now = date.getTime();
      //设置截止时间
      var str="2017/5/17 00:00:00";
      var endDate = new Date(str);
      var end = endDate.getTime();

      //时间差
      var leftTime = end-now;
      //定义变量 d,h,m,s保存倒计时的时间
      var d,h,m,s;
      if (leftTime>=0) {
        d = Math.floor(leftTime/1000/60/60/24);
        h = Math.floor(leftTime/1000/60/60%24);
        m = Math.floor(leftTime/1000/60%60);
        s = Math.floor(leftTime/1000%60);
      }
      //将倒计时赋值到p中
      document.getElementById("_d").innerHTML = d+"天";
      document.getElementById("_h").innerHTML = h+"时";
      document.getElementById("_m").innerHTML = m+"分";
      document.getElementById("_s").innerHTML = s+"秒";
      //递归每秒调用countTime方法，显示动态时间效果
      setTimeout(countTime,1000);

    }
  </script>
</head >
<body onload="countTime()" >
  <p>
    <span id="_d">00</span>
    <span id="_h">00</span>
    <span id="_m">00</span>
    <span id="_s">00</span>
  </p>
</body>
</html>

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A brief discussion on two ways to achieve countdown effects in JS (code examples)

Recommended study: " js tutorial》