> For the complete documentation index, see [llms.txt](https://developers.oxylabs.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developers.oxylabs.io/products/cn/web-scraper-api/features/custom-parser/writing-instructions-manually.md).

# 手动编写指令

虽然自定义解析器通过 AI 驱动的功能帮助你自动化数据解析，但你也可以使用 CSS 和 XPath 表达式手动编写解析指令。这让你可以 **处理边缘情况** 或 **自定义解析逻辑** 以适应特定场景。

创建任务时，自定义解析器需要以下必填参数：

* `parse` 设置为 `true`
* `parsing_instructions` 其中包含一个带有提取规则的 JSON 对象

当你对自定义解析逻辑满意后，可以将这些指令保存为可复用的 [解析器预设](/products/cn/web-scraper-api/features/custom-parser/parser-presets.md).

请查看下面我们的完整指南，其中可以找到实用示例、XPath 表达式的最佳实践，以及所有可用解析函数的完整参考。

{% content-ref url="/pages/f0599592eb013357024a5311a8b39c2e63e3cf58" %}
[解析指令示例](/products/cn/web-scraper-api/features/custom-parser/writing-instructions-manually/parsing-instruction-examples.md)
{% endcontent-ref %}

{% content-ref url="/pages/3aac6fc9ec9d5f1b4b4bf87d5a05ad6b0991ceb6" %}
[编写 XPath 表达式的提示](/products/cn/web-scraper-api/features/custom-parser/writing-instructions-manually/tips-for-writing-xpath-expressions.md)
{% endcontent-ref %}

{% content-ref url="/pages/b210c7fde99e3f92815c49348b7c1d7ea1c4d44c" %}
[解析函数列表](/products/cn/web-scraper-api/features/custom-parser/writing-instructions-manually/list-of-functions.md)
{% endcontent-ref %}

{% content-ref url="/pages/4676fed76a7d4066f1f6f839e8d4da500d6ee701" %}
[解析函数示例](/products/cn/web-scraper-api/features/custom-parser/writing-instructions-manually/list-of-functions/function-examples.md)
{% endcontent-ref %}


---

# Agent Instructions
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## 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://developers.oxylabs.io/products/cn/web-scraper-api/features/custom-parser/writing-instructions-manually.md?ask=<question>
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