js 倒计时

基本介绍

以下计时器满足两种业务逻辑，一个是根据页面时间倒计时，一个是指定时间倒计时。

根据页面时间倒计时

(function(){
    var startCountDown = function(){
        var hours = parseInt($("#hour").text());
        var minutes = parseInt($("#minute").text());
        var seconds = parseInt($("#second").text());
        if (seconds <= 0) {
            if (minutes <= 0) {
                if (hours <= 0) {
                    alert("时间结束！");
                    return ;
                } else {
                    hours--;
                }
                minutes = 59;
            } else {
                minutes--;
            }
            seconds = 59;
        } else {
            seconds--;
        }
        $("#second").html((seconds).toString().length > 1 ? seconds : "0" + seconds);
        $("#minute").html((minutes).toString().length > 1 ? minutes : "0" + minutes);
        $("#hour").html((hours).toString().length > 1 ? hours : "0" + hours);
        time = setTimeout(startCountDown, 1000);
    };
    window.startCountDown = startCountDown;
})();

---

指定时间倒计时

(function(){
    var seconds = 60; // 指定时间
    var startCountDown = function(){
        if (seconds <= 0) {
            console.log("获取超时!");
        } else {
            console.log("请耐心等待(" + (seconds--) + "s)");
        }
        time = setTimeout(startCountDown, 1000);
    };
    window.startCountDown = startCountDown;
})();