javascript - 在 JavaScript 中计算嵌套的 div

Question

嘿，我需要计算具有给定类名的嵌套 div。例如:

<div id = "divA">
    <div class = "anotherName"></div>
    <div class = "toBeCounted"></div>
    <div class = "someName"></div>
    <div class = "toBeCounted"></div>
    <div class = "toBeCounted"></div>
    <div class = ""></div>
</div>
<div id = "divB">
    <div class = ""></div>
    <div class = "toBeCounted"></div>
    <div class = ""></div>
    <div class = "toBeCounted"></div>
</div>

所以如果我想计算“toBeCounted”，我会得到 3 个 divA 和 2 个 divB。

Answer 1

您可以使用 .querySelectorAll() 并检查结果的长度:

var divAcount = document.querySelectorAll("#divA > .toBeCounted").length;

> 关系坚持 .toBeCounted 元素是 divA 的直接子元素。如果这不是您想要的，并且divA 中的any toBeCounted div 应该算在内，您只需省略>.