在 `package.json` 中安装 `body-parser` 模块, 然后在文件顶部 `require` 进来, 用变量 `bodyParser` 保存它。 通过中间件的 `bodyParser.urlencoded({extended: false})` 方法处理 URL 编码数据, Pass the function returned by the previous method call to `app.use()`. As usual, the middleware must be mounted before all the routes that depend on it.
**Note:** `extended` is a configuration option that tells `body-parser` which parsing needs to be used. When `extended=false` it uses the classic encoding `querystring` library. When `extended=true` it uses `qs` library for parsing.
When using `extended=false`, values can be only strings or arrays. The object returned when using `querystring` does not prototypically inherit from the default JavaScript `Object`, which means functions like `hasOwnProperty`, `toString` will not be available. The extended version allows more data flexibility, but it is outmatched by JSON.