睡在javascript for循环中

Question

我正在尝试创建一个计数器，该计数器每1秒更新一次。 我制作了一个后端函数，该函数每30秒返回一次，这用Ajax调用。 呼叫结果除以30，然后应每1秒更新一次计数器，持续30秒。 我将如何进行循环睡眠？

到目前为止，这是我的代码：

function getCount() {
    $.ajax({
        url: '@Url.Action("", "", new {area = ""})',
        type: 'POST',
        success: function (data) {
            var newTotalCount = data.totalCount;
            var newDanishCount = data.danishCount;
            var newNorwayCount = data.norwayCount;
            var newSwedenCount = data.swedenCount;
            var newUsCount = data.usCount;

            var currentTotalCount = $("#odoTotal").text().replace(/,/g, "").replace(/(\r\n|\n|\r)/gm, "");
            var currentDanishCount = $("#odoDk").text().replace(/,/g, "").replace(/(\r\n|\n|\r)/gm, "");
            var currentNorwayCount = $("#odoNo").text().replace(/,/g, "").replace(/(\r\n|\n|\r)/gm, "");
            var currentSwedenCount = $("#odoSe").text().replace(/,/g, "").replace(/(\r\n|\n|\r)/gm, "");
            var currentUsCount = $("#odoUs").text().replace(/,/g, "").replace(/(\r\n|\n|\r)/gm, "");

            var updateTotalCount = newTotalCount - currentTotalCount;
            var updateDanishCount = newDanishCount - currentDanishCount;
            var updateNorwayCount = newNorwayCount - currentNorwayCount;
            var updateSwedenCount = newSwedenCount - currentSwedenCount;
            var updateUsCount = newUsCount - currentUsCount;

            var updateTotalPerSecond = updateTotalCount / 30;
            var updateDanishPerSecond = updateDanishCount / 30;
            var updateNorwayPerSecond = updateNorwayCount / 30;
            var updateSwedenPerSecond = updateSwedenCount / 30;
            var updateUsPerSecond = updateUsCount / 30;


            getAllSales();

            for (var i = 0; i < 30; i++) {
                window.setTimeout(function() {
                    $("#odoTotal").html(currentTotalCount+updateTotalPerSecond);

                    $("#odoDk").html(currentDanishCount+updateDanishPerSecond);

                    $("#odoNo").html(currentNorwayCount+updateNorwayPerSecond);

                    $("#odoSe").html(currentSwedenCount+updateSwedenPerSecond);

                    $("#odoUs").html(currentUsCount+updateUsPerSecond);

                    currentTotalCount = $("#odoTotal").text().replace(/,/g, "").replace(/(\r\n|\n|\r)/gm, "");
                    currentDanishCount = $("#odoDk").text().replace(/,/g, "").replace(/(\r\n|\n|\r)/gm, "");
                    currentNorwayCount = $("#odoNo").text().replace(/,/g, "").replace(/(\r\n|\n|\r)/gm, "");
                    currentSwedenCount = $("#odoSe").text().replace(/,/g, "").replace(/(\r\n|\n|\r)/gm, "");
                    currentUsCount = $("#odoUs").text().replace(/,/g, "").replace(/(\r\n|\n|\r)/gm, "");


                }, 1000);

            }

        }
    });

}

Answer 1

我为此找到了解决方案

首先创建一个变量，您将要增加

var x = 0;

然后创建一个间隔，该间隔将在一段时间（例如5秒）后执行您想要的操作，这也会在每次运行时增加您的值x

var interval = setInterval(function() {
    if (x >= 5) { // just change 5 to 30
        console.log('Loop timeout ended');
        return clearInterval(interval);
    }
    // do what ever you want
    console.log('Current x: '+x);
    x++;
}, 5000); 

示例功能

function runTimeoutLoop(){
    var x = 0;
    var interval = setInterval(function() {
        if (x >= 5) { // just change 5 to 30
            console.log('Loop timeout ended');
            return clearInterval(interval);
        }
        // do what ever you want
        console.log('Current x: '+x);
        x++;
    }, 5000); 

}

演示版

Answer 2

如果您使用Firefox 53+或babel，则可以使用ES2017：

async function promiseTimeout(milliseconds) {
    await new Promise(resolve => setTimeout(()=>resolve(), milliseconds))
}

async function countDown(from) {
    while (from) {
        console.log(from--, 'seconds left');
        await promiseTimeout(1000);
    }
    alert('countdown done');
}

countDown(10);

这是通天塔。