windows webpack devServer报错 Error: listen address already in use 127.0.0.1:8090

webpack listen EADDRINUSE: address already in use

如果本地运行多个webpack项目会报错：

listen EADDRINUSE: address already in use :::8090

提示含义：地址端口已经被占用

注：8090指的是前一个项目的地址端口，但后一个项目默认也会用这个，所以就会冲突报错；

Administrator@PC-20190222QKVD MINGW64 ~/Desktop/webpack-demo

$ npm run dev

webpack-demo@1.0.0 dev C:UsersAdministratorDesktopwebpack-demo

webpack-dev-server --mode development nevents.js:174 throw er; // Unhandled \'error\' event Error: listen EADDRINUSE: address already in use 127.0.0.1:8090 at Server.setupListenHandle [as _listen2] (net.js:1270:14) at listenInCluster (net.js:1318:12) at GetAddrInfoReqWrap.doListen [as callback] (net.js:1451:7) at GetAddrInfoReqWrap.onlookup [as oncomplete] (dns.js:61:10) Emitted \'error\' event at: at emitErrorNT (net.js:1297:8) at process._tickCallback (internal/process/next_tick.js:63:19) \nnpm ERR! code ELIFECYCLE \nnpm ERR! errno 1 \nnpm ERR! webpack-demo@1.0.0 dev: webpack-dev-server --mode development \nnpm ERR! Exit status 1 \nnpm ERR! \nnpm ERR! Failed at the webpack-demo@1.0.0 dev script. \nnpm ERR! This is probably not a problem with npm. There is likely additional logging output above. \nnpm ERR! A complete log of this run can be found in: \nnpm ERR!     C:UsersAdministratorAppDataRoamingnpm-cache_logs2019-05-09T06_41_46_304Z-debug.log \nAdministrator@PC-20190222QKVD MINGW64 ~/Desktop/webpack-demo

解决方式：

1、关掉前一个项目的浏览器界面，再关掉前一个项目的编辑器环境，重新输入npm run dev即可；

2、如果上一个方法无效，说明端口还在后台运行，可以考虑命令强关，避免端口冲突，相关操作。

a、window + R调出命令框，输入：netstat -ano。

b、找到8090端口；输入命令后回车。

c、重新输入npm run dev运行项目即可。

d、上面太麻烦了，ctrl+c 直接退出就行（已经关闭8090端口），从新编译，端口8090就不会在被占用。