> For the complete documentation index, see [llms.txt](https://3440217568.gitbook.io/rxswift/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://3440217568.gitbook.io/rxswift/decision_tree/groupby.md).

# groupBy

**将源 `Observable` 分解为多个子 `Observable`，并且每个子 `Observable` 将源 `Observable` 中“相似”的元素发送出来**

![](/files/-MWlwRt5Iv3gBN5vhYIn)

**groupBy** 操作符将源 `Observable` 分解为多个子 `Observable`，然后将这些子 `Observable` 发送出来。

它会将元素通过某个键进行分组，然后将分组后的元素序列以 `Observable` 的形态发送出来。


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