JavaScript 倒计时器在 1 秒后卡住

Question

我需要创建一个javascript倒计时器，我一直在尝试使用setInterval方法来完成它，但是当我将秒数作为参数传递时，它会不断循环，这样它只会减少1秒然后停止。这是我的代码:

JavaScript:

var second = 120;
document.getElementById('timer').innerHTML = second;
function setTimer(second)
{
    second--;
    document.getElementById('timer').innerHTML = second;
    return second;
}
second = window.setInterval(setTimer, 1000, second); //Timer for user display

谢谢!

Answer 1

就这样做:

function setTimer(num) {
    //start the interval
    var counter = setInterval(function () {
        document.getElementById('timer').innerHTML = num; //write to div
        num-- || clearInterval(counter); //clear (stop) if its 0
    }, 1000);
}
setTimer(120);

演示::jsFiddle