执行ng build报错未依赖@angular/core，npm install遇EEXIST错误求助

Let's break down and fix these two issues one by one—starting with the blocking npm error first, then addressing the missing @angular/core dependency.

1. Resolve the npm ERR! code EEXIST Error #

This error pops up because the ng command file at /usr/local/bin/ng already exists, and npm can't overwrite it during the global CLI installation. Here's how to clear this conflict:

• First, delete the existing ng file to make space for the fresh installation:

  sudo rm /usr/local/bin/ng
  

• Next, clear npm's cache to get rid of any corrupted or outdated cached files that might cause issues:

  npm cache clean --force
  

• Since your Node.js version is v9.10.1 (which is older), you'll need a compatible Angular CLI version—newer CLI releases won't play nice with Node v9. Install Angular CLI 7.x (the latest stable version that supports Node v9):

  npm install -g @angular/cli@7.3.9
  

• Verify the installation worked by checking the CLI version:

  ng --version
  

2. Fix the "You seem to not be depending on '@angular/core'" Error #

This error means your project's local dependencies are either missing, corrupted, or @angular/core isn't properly listed in your package.json. Let's fix that:

• Navigate to your project's root directory first.
• Delete the local node_modules folder and package-lock.json file to wipe out any corrupted dependency data:

  rm -rf node_modules package-lock.json
  

• Reinstall all local project dependencies from scratch:

  npm install
  

• If @angular/core still doesn't show up in your package.json after reinstalling, manually add it (match the version to your Angular CLI—for CLI 7.x, use Angular core 7.x):

  npm install @angular/core@7.2.16 --save
  

• Finally, try building your project again:

  ng build
  

A quick heads-up: Node.js v9 is no longer supported, so if you can spare the time, upgrading to a newer LTS version (like Node 14 or 16) will help avoid future compatibility headaches. But the steps above should get your current setup working smoothly.

内容的提问来源于stack exchange，提问作者Floriane