当单击一个减少值的按钮时，如何阻止它减少到负值范围

Question

（第一个问题！）

我（试图）创建一个点击游戏。单击按钮时，金值应减少 10。这是有效的。但是，我想阻止它减少为零。

例如（如果单击按钮 || 如果金数 >= 0）执行代码。其他：错误消息（这不是实际代码，只是我的想法）

我尝试了几种方法，但似乎都不起作用

有任何想法吗？（我不完全确定这是否可行，因为当您单击按钮时，它会按该数字递减，然后检查值是否为零？我想？那会不会是一个无限循环？）

(BeggarCount, BeggarCost, oText 和 oCount) 的变量之前都在 HTML 中定义过。正如我所说，代码确实有效，只是停在零

代码：

        <script type="text/javascript" language="javascript">

            var vButton = document.getElementById("AddBeggar");

            var vText = document.getElementById("BeggarCount");

            var vcText = document.getElementById("BeggarCost");

            var vcost = 10

            var vcount = 0;

            var vprice = 10;

            if (vButton.addEventListener('click') || ocount >= 10) {

                vText.innerHTML = vcount += 1;

                vcText.innerHTML = vcost += 1;

                oText.innerHTML = oincrement += 1;

                oText.innerHTML = ocount -= vprice;

                vprice += 1;

            }, false);

当我尝试这个时，根本没有任何反应。

Answer 1

我想您应该更改检查黄金当前价值的 if 子句，例如：if (vButton.addEventListener('click')&nbsp; && ocount >= 10) {&nbsp; &nbsp; vText.innerHTML = vcount += 1;&nbsp; &nbsp; vcText.innerHTML = vcost += 1;&nbsp; &nbsp; oText.innerHTML = oincrement += 1;&nbsp; &nbsp; oText.innerHTML = ocount -= vprice;&nbsp; &nbsp; vprice += 1;}, false);

Answer 2

刚刚做到了！！&nbsp; &nbsp; &nbsp; &nbsp; <script type="text/javascript" language="javascript">&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; var vButton = document.getElementById("AddBeggar");&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; var vText = document.getElementById("BeggarCount");&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; var vcText = document.getElementById("BeggarCost");3&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; var vcost = 10&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; var vcount = 0;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; var vprice = 10;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; vButton.addEventListener('click', function(i, a) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (ocount >= vcost) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; vText.innerHTML = vcount += 1;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; vcText.innerHTML = vcost += 1;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; oText.innerHTML = oincrement += 1;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; oText.innerHTML = ocount -= vprice;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; vprice += 1;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }, false);&nbsp; &nbsp; &nbsp; &nbsp; </script>这段代码有效！！所有变量都相同