使用ng update从Angular 5升级到Angular 6遇问题，求解决方案

阿华AIGC实验室

2026-5-27

Fixing ng update Issues When Upgrading from Angular 5 to 6

Hey there! Let's work through this upgrade problem together. Based on the most common hurdles developers face when moving from Angular 5 to 6, here's a step-by-step solution to get your ng update command working again:

Step 1: Upgrade Angular CLI to a Compatible Version

Angular 6 requires CLI v6.x, but Angular 5 uses the older angular-cli (not the scoped @angular/cli package). Let's fix that first:

Uninstall the old global CLI:
```
npm uninstall -g angular-cli
```
Clear your npm cache to avoid leftover conflicts:
```
npm cache clean --force
```
(Note: For npm 5+, you can use npm cache verify instead if clean --force throws errors)
Install the correct global CLI v6:
```
npm install -g @angular/cli@6
```
Update the local CLI in your project:
```
npm install @angular/cli@6 --save-dev
```

Step 2: Clean Up Dependencies and Run Targeted Updates

Old dependencies can block the update process. Let's reset and upgrade core packages:

Delete your node_modules folder and package-lock.json (or yarn.lock if using Yarn) to eliminate conflicting cached dependencies.
Run the core Angular upgrade command, specifying the target version:
```
ng update @angular/core@6
```
Angular 6 requires RxJS 6.x and TypeScript 2.7+. If you see errors related to these, install the compatible versions manually:
```
npm install rxjs@6 rxjs-compat@6 --save
npm install typescript@2.7 --save-dev
```
(The rxjs-compat package helps keep old RxJS code working while you refactor to the v6 syntax)

Step 3: Migrate Configuration Files

Angular 6 replaced .angular-cli.json with angular.json. Let's auto-migrate this:

ng update @angular/cli@6 --from=1 --to=6 --migrate-only

This command will convert your old CLI config to the new format without updating other packages.

Step 4: Verify and Troubleshoot Remaining Issues

Reinstall all dependencies:
```
npm install
```
Start your project to check if it runs:
```
ng serve
```
If you still see errors, look for third-party libraries in your package.json that might not support Angular 6. You'll need to upgrade those packages to versions explicitly marked as compatible with Angular 6 (check their npm pages or documentation for details).