用JavaScript中的getElementsByClass更改光标？

Question

I want my cursor to be a hand when hovering over elements with a class of "one" after clicking a button. 在单击按钮后，将鼠标悬停在具有“ one”类的元素上时，我希望光标成为指针。 Here is my code 这是我的代码

<!DOCTYPE html>
<html>
<head>
<script type="text/javascript" language="JavaScript">
    function cursor()
    {
    document.getElementByClass("one").style.cursor="pointer";
    }
</script>
<h1 class="one">Mouse over this text!</h1>
</head>
<body>
<p class="fff">not me!</p>
<button type="button" onclick="cursor()">Change cursor</button>
</body>
</html>

It has only worked so far when I change it to getElementById("one") and changed one of the elements from a "one" class to a "one" id. 到目前为止，仅当我将其更改为getElementById（“ one”）并将元素之一从“一个”类更改为“一个” id时，它才起作用。 Why is this not working with class as well? 为什么这也不适用于课堂？

Answer 1

The reason it didn't work is because getElementsByClassName() returns a node-list of multiple elements, which you have to access individually: 它不起作用的原因是因为getElementsByClassName()返回了多个元素的节点列表，您必须分别对其进行访问：

function cursor() {
    var elems = document.getElementByClass("one");
    for (var i=0, len=elems; i<len; i++) {
        elems[i].style.cursor = 'pointer';
    }
}

But there really is no need to do this with JavaScript, use CSS: 但是实际上不需要使用JavaScript来执行此操作，请使用CSS：

.one {
    cursor: pointer;
}

Answer 2

You could avoid using JavaScript here by using CSS. 您可以在此处通过使用CSS避免使用JavaScript。

.one {
    cursor: pointer;
}

The reason the JavaScript didn't automatically work is because getElementById() (if successful) returns a single reference to an element, of which you can set properties on. JavaScript无法自动运行的原因是因为getElementById() （如果成功）返回对元素的单个引用，可以在其上设置属性。

The reason switching to getElementsByClassName() didn't automatically work is because it returns a NodeList , a collection of elements. 切换到getElementsByClassName()不能自动工作的原因是因为它返回NodeList ，这是元素的集合。 This collection is like an array, and you must access its numbered properties to access the references to the elements it matched. 该集合就像一个数组，您必须访问其编号属性才能访问对其匹配的元素的引用。

用JavaScript中的getElementsByClass更改光标？

问题描述

2 个解决方案

解决方案1
3 2012-10-20 21:07:25

解决方案2
2 2012-10-20 21:05:16

用JavaScript中的getElementsByClass更改光标？

问题描述

2 个解决方案

解决方案1 3 2012-10-20 21:07:25

解决方案2 2 2012-10-20 21:05:16

解决方案1
3 2012-10-20 21:07:25

解决方案2
2 2012-10-20 21:05:16