以下语法用于根据标记和类名选取元素。

And the following syntax for selecting by tag and class name.

youdao

ExtJS使用类似的方式，用以下语法根据ID选取元素。

ExtJS works in a similar manner, with the following syntax for selecting an element by id.

youdao

根据标记名选取元素非常有用，但如果只是想根据css类选择一个元素子集，该怎么办呢？

Selecting elements by a tag name is useful, but what if you only want to select a subset of elements, based on their CSS class?

youdao

Having done that, I could do the same thing, so I suppose I take this branch, I can pick a spot like, say, this one, and look there.

再从其中随即选取一个元素，比如这一个，请注意，如果相等则结束，如果不相等的话就在它的左边或右边找。

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