如何使用jQuery选择单个子元素?

Using jQuery how do I select a single child element? I've looked at the Traversing API and know I can select all the immediate children img elements like this:

如何使用jQuery选择单个子元素?我查看了遍历API，知道我可以选择所有直接的子img元素如下:

$(this).children('img');

And to select the first child img element I could use a subscript like this:

要选择第一个子img元素，我可以使用如下的下标:

$(this).children('img')[0];

But I guess I'm kind of surprised I can't do this:

但我想我有点惊讶我不能这么做:

$(this).child('img'); // no subscript, returns single element

Or have I missed something?

还是我漏掉了什么?

4 个解决方案

#1

No. Every jQuery function returns a jQuery object, and that is how it works. This is a crucial part of jQuery's magic.

不。每个jQuery函数都返回一个jQuery对象，这就是它的工作原理。这是jQuery魔术的关键部分。

If you want to access the underlying element, you have three options...

如果您想访问底层元素，您有三个选项…

Do not use jQuery
不使用jQuery
Use [0] to reference it
使用[0]引用它
Extend jQuery to do what you want...

扩展jQuery来实现您想要的…
```
$.fn.child = function(s) {
    return $(this).children(s)[0];
}
```

#2

I think what you want to do is this:

我认为你想做的是:

$(this).children('img').eq(0);

this will give you a jquery object containing the first img element, whereas

这将给您一个包含第一个img元素的jquery对象，反之亦然。

$(this).children('img')[0];

will give you the img element itself.

会给你img元素本身。

#3

Maybe in this way?

也许以这种方式?

$('img', this)[0]

#4

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#1