如何编写.nvmrc实现Node版本自动切换及Angular项目自动切换Node版本

Got it, let's cover two reliable methods to automate Node version switching between your AngularJS 4.4.7 and Angular 6 projects—one using NVM's built-in .nvmrc (since you already use NVM, this is the most straightforward) and another with avn and .node-version.

Method 1: Use .nvmrc with NVM (No Extra Tools Needed) #

NVM has native support for a .nvmrc file to auto-switch versions when you enter a project directory. Here's how to set it up:

1. Confirm required Node versions for each project

   • AngularJS 4.4.7 requires Node 6.9.0+; we recommend Node 8.x for stability (e.g., v8.17.0).
   • Angular 6 requires Node 8.9.0+; Node 10.x works well (e.g., v10.24.1).
   • Manually switch to each version first with nvm use <version> and verify with node -v.

2. Create the .nvmrc file in each project root

   • Open your terminal, navigate to your AngularJS project root, and run:

     echo "v8.17.0" > .nvmrc
     

   • Repeat for your Angular 6 project, replacing the version with your target (e.g., echo "v10.24.1" > .nvmrc).
   • Alternatively, manually create a plain text file named .nvmrc in the project root, and paste just the version number (with or without the v prefix—NVM recognizes both).

3. Configure your terminal to auto-load the version

   • For Bash: Open your ~/.bashrc file and add this snippet:

     cd() {
       builtin cd "$@"
       if [ -f .nvmrc ]; then
         nvm use
       fi
     }
     

   • For Zsh: Open your ~/.zshrc file and add the same snippet.
   • Save the file, then restart your terminal or run source ~/.bashrc (or source ~/.zshrc) to apply the changes.

4. Test it out

   • Navigate to either project directory—your terminal will automatically run nvm use and switch to the version specified in .nvmrc. You’ll see a confirmation message like Now using node v8.17.0 (npm v6.14.13).

Method 2: Use avn with .node-version #

If you prefer avn, here's how to set it up with .node-version files:

1. Install avn and its NVM integration

   • Run this command to install avn globally:

     npm install -g avn avn-nvm
     

   • Initialize avn by running:

     avn setup
     

   • Follow the prompts to update your shell configuration file (Bash/Zsh). This ensures avn runs automatically when you open your terminal.

2. Create the .node-version file in each project root

   • Navigate to your AngularJS project root and run:

     echo "8.17.0" > .node-version
     

   • Note: Unlike .nvmrc, avn uses the version number without the v prefix.
   • Repeat for your Angular 6 project with your target version (e.g., echo "10.24.1" > .node-version).
   • You can also manually create the file and paste just the version number.

3. Test the auto-switch

   • Restart your terminal, then navigate to either project directory. avn will automatically detect the .node-version file and tell NVM to switch to the specified version. Verify with node -v.

Important Notes #

• Pre-install Node versions: Make sure you’ve already installed the required Node versions via NVM (e.g., nvm install 8.17.0) before setting up auto-switching—otherwise, you’ll get an error saying the version isn’t installed.
• Stick to Angular’s official requirements: Always cross-check the Node version compatibility for your Angular/AngularJS version to avoid build or runtime issues.

内容的提问来源于stack exchange，提问作者Janani Hariharan