> For the complete documentation index, see [llms.txt](https://socket.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://socket.gitbook.io/docs/4-fu-wu-duan-apiserverapi/4.2-ming-ming-kong-jian-namespace/flag_binary.md).

# 4.2.13 二进制标志位 flag\_binary

(二进制传输可以提高性能)

指定发出的数据中是否存在二进制数据。指定时提高性能。可以是 `true` 或者 `false`

```javascript
io.binary(false).emit('an event',{some:'data'});
```