### 服务端 ``` cnpm install --save socket.io ``` ### 客户端 ``` 两种方式引入socket.io.js 官方文档 A standalone build of the client is exposed by default by the server at `/socket.io/socket.io.js`. It can also be served from a CDN, like [cdnjs](https://cdnjs.com/libraries/socket.io). 1. /socket.io/socket.io.js 2. cdn ```