Version: 4.x

客户端安装

info

目前最新版本是 4.7.5，于 2024 年 3 月发布。

¥The latest release is currently 4.7.5, released in March 2024.

你可以找到发行说明此处。

¥You can find the release notes here.

版本兼容性

¥Version compatibility

下面是服务器端和 JS 客户端的兼容性表：

¥Here is the compatibility table between the server and the JS client:

JS 客户端版本	Socket.IO 服务器版本
JS 客户端版本	1.x	2.x	3.x	4.x
1.x	是的	不	不	不
2.x	不	是的	是的¹	是的¹
3.x	不	不	是的	是的
4.x	不	不	是的	是的

[1] 是的，与允许 EIO3：true 一起

¥[1] Yes, with allowEIO3: true

请查看相关的迁移指南：

¥Please check the associated migration guides:

v2 到 v3
¥v2 to v3
v3 到 v4
¥v3 to v4

浏览器支持

¥Browser support

Socket.IO 确实支持 IE9 及以上版本。不再支持 IE 6/7/8。

¥Socket.IO does support IE9 and above. IE 6/7/8 are not supported anymore.

借助出色的 Sauce Labs 平台测试了浏览器兼容性：

¥Browser compatibility is tested thanks to the awesome Sauce Labs platform:

Browser support

安装

¥Installation

独立构建

¥Standalone build

默认情况下，Socket.IO 服务器在 /socket.io/socket.io.js 处公开客户端包。

¥By default, the Socket.IO server exposes a client bundle at /socket.io/socket.io.js.

io 将被注册为全局变量：

¥io will be registered as a global variable:

<script src="/socket.io/socket.io.js"></script>
<script>
  const socket = io();
</script>

如果你不需要此功能（请参阅下面的其他选项），你可以在服务器端禁用该功能：

¥If you don't need this (see other options below), you can disable the functionality on the server side:

const { Server } = require("socket.io");

const io = new Server({
  serveClient: false
});

来自 CDN

¥From a CDN

你还可以包含来自 CDN 的客户端打包包：

¥You can also include the client bundle from a CDN:

<script src="https://cdn.socket.io/4.7.5/socket.io.min.js" integrity="sha384-2huaZvOR9iDzHqslqwpR87isEmrfxqyWOF7hr7BY6KG0+hVKLoEXMPUJw3ynWuhO" crossorigin="anonymous"></script>

Socket.IO 也可以从其他 CDN 获得：

¥Socket.IO is also available from other CDN:

有多种打包包可供选择：

¥There are several bundles available:

名称	尺寸	描述
套接字.io.js	34.7 kB 压缩	未缩小版本，带有 debug
socket.io.min.js	最小 14.7 kB+gzip	量产版，不含 debug
socket.io.msgpack.min.js	最小 15.3 kB+gzip	量产版，不带 debug，带消息包解析器

debug 包允许将调试信息打印到控制台。你可以找到更多信息此处。

¥The debug package allows to print debug information to the console. You can find more information here.

在开发过程中，我们建议使用 socket.io.js 打包包。通过设置 localStorage.debug = 'socket.io-client:socket'，客户端接收到的任何事件都将打印到控制台。

¥During development, we recommend using the socket.io.js bundle. By setting localStorage.debug = 'socket.io-client:socket', any event received by the client will be printed to the console.

对于生产，请使用 socket.io.min.js 打包包，这是一个不包括调试包的优化构建。

¥For production, please use the socket.io.min.js bundle, which is an optimized build excluding the debug package.

来自 NPM

¥From NPM

Socket.IO 客户端与 webpack 或 browserify 等打包器兼容。

¥The Socket.IO client is compatible with bundlers like webpack or browserify.

NPM
Yarn
pnpm

npm install socket.io-client

yarn add socket.io-client

pnpm add socket.io-client

客户端也可以从 Node.js 运行。

¥The client can also be run from Node.js.

注意：由于上述原因，你可能希望从浏览器打包包中排除调试。通过 webpack，你可以使用 webpack-remove-debug。

¥Note: for the reasons cited above, you may want to exclude debug from your browser bundle. With webpack, you can use webpack-remove-debug.

TypeScript 用户注意事项：这些类型现在包含在 socket.io-client 包中，因此不再需要 @types/socket.io-client 中的类型，并且实际上可能会导致错误：

¥Note for TypeScript users: the types are now included in the socket.io-client package and thus the types from @types/socket.io-client are not needed anymore and may in fact cause errors:

Object literal may only specify known properties, and 'extraHeaders' does not exist in type 'ConnectOpts'

杂项

¥Miscellaneous

依赖树

¥Dependency tree

客户端的基本安装包括 9 个软件包，其中 5 个由我们团队维护：

¥A basic installation of the client includes 9 packages, of which 5 are maintained by our team:

└─┬ socket.io-client@4.7.2
  ├── @socket.io/component-emitter@3.1.0
  ├─┬ debug@4.3.4
  │ └── ms@2.1.2
  ├─┬ engine.io-client@6.5.2
  │ ├── @socket.io/component-emitter@3.1.0 deduped
  │ ├── debug@4.3.4 deduped
  │ ├── engine.io-parser@5.2.1
  │ ├─┬ ws@8.11.0
  │ │ ├── UNMET OPTIONAL DEPENDENCY bufferutil@^4.0.1
  │ │ └── UNMET OPTIONAL DEPENDENCY utf-8-validate@^5.0.2
  │ └── xmlhttprequest-ssl@2.0.0
  └─┬ socket.io-parser@4.2.4
    ├── @socket.io/component-emitter@3.1.0 deduped
    └── debug@4.3.4 deduped

传递版本

¥Transitive versions

engine.io-client 包带来了负责管理底层连接（HTTP 长轮询或 WebSocket）的引擎。也可以看看：工作原理

¥The engine.io-client package brings the engine that is responsible for managing the low-level connections (HTTP long-polling or WebSocket). See also: How it works

`socket.io-client` 版本	`engine.io-client` 版本	`ws` 版本¹
`4.7.x`	`6.5.x`	`8.17.x`
`4.6.x`	`6.4.x`	`8.11.x`
`4.5.x`	`6.2.x`	`8.2.x`
`4.4.x`	`6.1.x`	`8.2.x`
`4.3.x`	`6.0.x`	`8.2.x`
`4.2.x`	`5.2.x`	`7.4.x`
`4.1.x`	`5.1.x`	`7.4.x`
`4.0.x`	`5.0.x`	`7.4.x`
`3.1.x`	`4.1.x`	`7.4.x`
`3.0.x`	`4.0.x`	`7.4.x`
`2.5.x`	`3.5.x`	`7.5.x`
`2.4.x`	`3.5.x`	`7.5.x`

[1] 仅适用于 Node.js 用户。在浏览器中，使用原生 WebSocket API。

¥[1] for Node.js users only. In the browser, the native WebSocket API is used.

版本兼容性​

浏览器支持​

安装​

独立构建​

来自 CDN​

来自 NPM​

杂项​

依赖树​

传递版本​