# 1-3 服务HTML(Serving HTML)
到目前为止，在 `index.js` 中我们调用了 `res.end`并传递一个HTML字符串。如果我们将整个应用程序的HTML放在那里，我们代码看起来会很混乱，相反，我们将创建一个`index.html`文件并提供服务。
让我们重构下，使用`sendFile`替换下路由处理程序：
```javascript
app.get('/',(req,res)=>{
res.sendFile(__dirname+'/index.html')
})
```
在`index.html`补充下内容，如下：
```markup
Socket.IO chat
```
如果你重启下(ctrl+c 关闭node服务，然后再次运行`node index.js`)进程和刷新页面，你应该看到如下：
---
# Agent Instructions: Querying This Documentation
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Perform an HTTP GET request on the current page URL with the `ask` query parameter:
```
GET https://socket.gitbook.io/docs/1-zhi-nan-guide/serving_html.md?ask=
```
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.
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