> 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/4.3-socket/flag_volatile.md).

# 4.3.23 flag\_volatile

为后续事件发出设置一个修饰符，如果客户端没有准备好接收消息（由于网络缓慢或其他问题，或者由于它们通过长轮询连接并且处于请求响应周期的中间），则事件数据可能会丢失。

```javascript
io.on('connection',socket=>{
    socket.volatile.emit('an event',{some:"data"}); //客户可能会收到，也可能不会收到。
})
```


---

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