1.查询当前配置的镜像

npm get registtry  或  yarn get registtry

https://registry.npmjs.org/

2.设置成淘宝镜像

 npm config set registry https://registry.npm.taobao.org/  或  yarn config set registry https://registry.npm.taobao.org/

3.换成原来的

 npm config set registry https://registry.npmjs.org/   或   yarn config set registry https://registry.npmjs.org/