> For the complete documentation index, see [llms.txt](https://surge.mitsea.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://surge.mitsea.com/scripting/cron.md).

# 计划任务

#### 计划任务 (cron)

在指定的时间执行脚本。该值应为 cron 表达式，这是一个由五或六个子表达式（字段）组成的字符串，用于描述排程的具体细节。

一些 cron 表达式示例：

* 每天凌晨 2 点: `0 2 * * *`
* 每天早上 5 点和下午 5 点: `0 5,17 * * *`
* 每分钟: `* * * * *`
* 每秒: `* * * * * *`
* 每个星期日下午 5 点: `0 17 * * sun`
* 每 10 分钟: `*/10 * * * *`

只有一个传入参数：`$cronexp`。

请调用 `$done()` 以完成执行。

一个简单的例子：

```javascript
// cron "0 2 * * *" script-path=cron.js
$surge.setSelectGroupPolicy('Group', 'Proxy');
$done();
```

#### 附加 API (Additional API)

* `$cronexp`: cron 表达式字符串。


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# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## 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, and the optional `goal` query parameter:

```
GET https://surge.mitsea.com/scripting/cron.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

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.