我正在尝试制作一个 JavaScript 计时器,启动后就会开始计数。计时器只是从单击开始按钮到单击结束按钮的视觉引用。
我在网上找到了一个非常适合倒计时的插件,但我正在尝试修改它以进行倒计时。
我在未来对日期方式进行了硬编码。我现在试图让计时器开始计时到该日期。每次单击开始按钮时都会重置。
这是我正在使用的功能。它可以完美地倒计时,但我不知道如何扭转它。
我认为这与计算差异的方式有关,但我相信它实际上发生在 //calculatedates
部分。
有没有一种简单的方法可以反转这个数学并让它计数?
fiddle :http://jsfiddle.net/xzjoxehj/
var currentDate = function () {
// get client's current date
var date = new Date();
// turn date to utc
var utc = date.getTime() + (date.getTimezoneOffset() * 60000);
// set new Date object
var new_date = new Date(utc + (3600000*settings.offset))
return new_date;
};
function countdown () {
var target_date = new Date('12/31/2020 12:00:00'), // Count up to this date
current_date = currentDate(); // get fixed current date
// difference of dates
var difference = current_date - target_date;
// if difference is negative than it's pass the target date
if (difference > 0) {
// stop timer
clearInterval(interval);
if (callback && typeof callback === 'function') callback();
return;
}
// basic math variables
var _second = 1000,
_minute = _second * 60,
_hour = _minute * 60,
_day = _hour * 24;
// calculate dates
var days = Math.floor(difference / _day),
hours = Math.floor((difference % _day) / _hour),
minutes = Math.floor((difference % _hour) / _minute),
seconds = Math.floor((difference % _minute) / _second);
// fix dates so that it will show two digets
days = (String(days).length >= 2) ? days : '0' + days;
hours = (String(hours).length >= 2) ? hours : '0' + hours;
minutes = (String(minutes).length >= 2) ? minutes : '0' + minutes;
seconds = (String(seconds).length >= 2) ? seconds : '0' + seconds;
// set to DOM
//
};
// start
var interval = setInterval(countdown, 1000);
};
最佳答案
var original_date = currentDate();
var target_date = new Date('12/31/2020 12:00:00'); // Count up to this date
var interval;
function resetCountdown() {
original_date = currentDate();
}
function stopCountdown() {
clearInterval(interval);
}
function countdown () {
var current_date = currentDate(); // get fixed current date
// difference of dates
var difference = current_date - original_date;
if (current_date >= target_date) {
// stop timer
clearInterval(interval);
if (callback && typeof callback === 'function') callback();
return;
}
// basic math variables
var _second = 1000,
_minute = _second * 60,
_hour = _minute * 60,
_day = _hour * 24;
// calculate dates
var days = Math.floor(difference / _day),
hours = Math.floor((difference % _day) / _hour),
minutes = Math.floor((difference % _hour) / _minute),
seconds = Math.floor((difference % _minute) / _second);
// fix dates so that it will show two digets
days = (String(days).length >= 2) ? days : '0' + days;
hours = (String(hours).length >= 2) ? hours : '0' + hours;
minutes = (String(minutes).length >= 2) ? minutes : '0' + minutes;
seconds = (String(seconds).length >= 2) ? seconds : '0' + seconds;
// set to DOM
//
};
// start
interval = setInterval(countdown, 1000);
};
关于JavaScript 计数计时器,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/32389881/