javascript - 停止 switch 方法内的嵌套 if 循环 | JavaScript

Question

过去几天，我和我的 friend 们在开发应用程序方面获得了很大的乐趣，唯一的问题是我们都不懂 JavaScript。到目前为止一切都很顺利。我从谷歌搜索中学到了很多东西，但我似乎无法解决这个问题。所以我们有一个调用函数的下拉菜单，

select id="vg" class="dropdown" onchange="vgchosen.call(this, event)">

这让我们回到了名为 vgchosen 的函数。在此函数中，有一个 switch 方法可以帮助评估所选的下拉菜单选项。

function vgchosen(event) {
alert(this.options[this.selectedIndex].text);
var vgc = document.getElementById("vg").selectedIndex;
var y = document.getElementById("vg").options;


switch (y[vgc].text) {
case "Action":
    var actionvgc = [
    "You should play |Skyrim",
    "You should play |Killing Floor 2",
    "You Should play |Counter Strike Global Offensive",
    "You should play |Left 4 Dead",
    "You should play |House of the Dead",
    "You should play |Elite: Dangerous",
    "You should play |Middle Earth: Shadow of Mordor",
    "You should play |Crypt of the Necro Dancer",
    "You should play |The Witcher 3: Wild Hunt",
    "You should play |Dark Souls",
    ];
    setInterval(function() {
        var i = Math.round((Math.random()) * actionvgc.length);
        if (i == actionvgc.length) --i;
        $("#actionvgc").html(actionvgc[i]);
        }, 1 * 1000);
        break;


case "Shooter":
    var shootervgc = [
    "You should play |Skyri",
    "You should play |Killing Floor ",
    "You Should play |Counter Strike Global Offensiv",
    "You should play |Left 4 Dea",
    "You should play |House of the Dea",
    "You should play |Elite: Dangerou",
    "You should play |Middle Earth: Shadow of Mordo",
    "You should play |Crypt of the Necro Dance",
    "You should play |The Witcher 3: Wild Hun",
    "You should play |Dark Soul",
    ];
    setInterval(function() {
        var i = Math.round((Math.random()) * shootervgc.length);
        if (i == shootervgc.length) --i;
        $("#actionvgc").html(shootervgc[i]);
    }, 1 * 1000);
    break;
}
}

当您通过选项选择启动该功能时，一切正常，您每秒都会给出一个新的游戏创意。当你想切换到不同的选项时，问题就出现了。如果您选择射击游戏(游戏的区别在于最后一个字母都丢失了)，它将同时显示两个游戏创意。当新循环开始时如何停止第一个循环？

编辑:#actionvgc 是显示文本的位置。可以在这里看到

<div id="actionvgc">"Hello World! im FLi!"</div>

Answer 1

setInterval() 函数返回一个标识该特定计时器的值。您可以稍后使用 clearInterval() 来停止它。

var timerId; // should probably be global

// ...

clearInterval(timerId); // clear prev timer
timerId = setInterval(function() { /* ... */ }, 1000);