Question

我尝试在页面上添加倒计时，但根本没有显示。这是HTML

<p id="countdown"></p>

这是我的javascript :(更新）

var countDownDate = new Date("Sep 5, 2018 15:37:25").getTime();

// Update the count down every 1 second
var x = setInterval(function() {

    // Get todays date and time
    var now = new Date().getTime();

    // Find the distance between now an the count down date
    var distance = countDownDate - now;

    // Time calculations for days, hours, minutes and seconds
    var days = Math.floor(distance / (1000 * 60 * 60 * 24));
    var hours = Math.floor((distance % (1000 * 60 * 60 * 24)) / (1000 * 60 * 60));
    var minutes = Math.floor((distance % (1000 * 60 * 60)) / (1000 * 60));
    var seconds = Math.floor((distance % (1000 * 60)) / 1000);

    // Display the result in the element with id="demo"
    document.getElementById("countdown").innerHTML = days + "d " + hours + "h "
+ minutes + "m " + seconds + "s ";

    // If the count down is finished, write some text 
    if (distance < 0) {
        clearInterval(x);
    }
},  1000);

Answer 1

setInterval，与setTimeout类似，需要2个参数：回调函数和延迟（以毫秒为单位）。

setInterval(function() {
    alert('2 seconds have elapsed!');
}, 2000);

你忘了以毫秒为单位给出延迟。有了它，你的脚本运行正常。

＆＃13;

var countDownDate = new Date("Sep 5, 2018 15:37:25").getTime();

// Update the count down every 1 second
var x = setInterval(function() {

  // Get todays date and time
  var now = new Date().getTime();

  // Find the distance between now an the count down date
  var distance = countDownDate - now;

  // Time calculations for days, hours, minutes and seconds
  var days = Math.floor(distance / (1000 * 60 * 60 * 24));
  var hours = Math.floor((distance % (1000 * 60 * 60 * 24)) / (1000 * 60 * 60));
  var minutes = Math.floor((distance % (1000 * 60 * 60)) / (1000 * 60));
  var seconds = Math.floor((distance % (1000 * 60)) / 1000);

  // Display the result in the element with id="demo"
  document.getElementById("countdown").innerHTML = days + "d " + hours + "h " +
    minutes + "m " + seconds + "s ";

  // If the count down is finished, write some text 
  if (distance < 0) {
    clearInterval(x);
    document.getElementById("countdown").innerHTML = "EXPIRED";
  }
}, 1000);

＆＃13;

<p id="countdown"></p>

＆＃13;

Javascript倒计时不显示

1 个答案: