事情是这样的，我今天准备安装element ui库，但是键入命令报错了。

于是我在网上找了一堆教程，什么更换npm源等，都无果。

最后我使用以下方法成功解决！

报错问题

• 首先打开终端，输入如下命令。

  npm i element-ui -S
  

• 然后出现报错信息。

  npm WARN deprecated core-js@2.6.12: core-js@<3.4 
  is no longer maintained and not recommended for usage due to the number of issues. Because of the 
  V8 engine whims, feature detection in old core-js versions could cause a slowdown up to 100x even 
  if nothing is polyfilled. Please, upgrade your dependencies to the actual version of core-js.     
  -v15 not found
  npm ERR! 404
  npm ERR! 404  '@vue/vue-loader-v15@15.9.8' is not in the npm registry.
  npm ERR! 404 You should bug the author to publish it (or use the name yourself!)
  npm ERR! 404 It was specified as a dependency of '@vue/cli-service'
  npm ERR! 404
  npm ERR! 404 Note that you can also install from a
  npm ERR! 404 tarball, folder, http url, or git url.
  npm ERR! A complete log of this run can be found in:
  npm ERR!     C:\Users\86132\AppData\Roaming\npm-cache\_logs\2022-03-17T05_34_59_509Z-debug.log
  

  

解决方法

• 于是我删除了整个node_modules。

  整个删掉！

• 紧接着再输入如下命令。

  npm i element-ui -S
  

• 安装成功。