# 07 - 操作 channel 的情况总结

总结一下操作 channel 的结果：

| 操作      | nil channel | closed channel | not nil, not closed channel                           |
| ------- | ----------- | -------------- | ----------------------------------------------------- |
| close   | panic       | panic          | 正常关闭                                                  |
| 读 <- ch | 阻塞          | 读到对应类型的零值      | 阻塞或正常读取数据。缓冲型 channel 为空或非缓冲型 channel 没有等待发送者时会阻塞     |
| 写 ch <- | 阻塞          | panic          | 阻塞或正常写入数据。非缓冲型 channel 没有等待接收者或缓冲型 channel buf 满时会被阻塞 |

总结一下，发生 panic 的情况有三种：向一个关闭的 channel 进行写操作；关闭一个 nil 的 channel；重复关闭一个 channel。

读、写一个 nil channel 都会被阻塞。


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://qcrao91.gitbook.io/go/channel/cao-zuo-channel-de-qing-kuang-zong-jie.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.