使用PrimeNg遇@angular/core找不到及元数据版本不匹配问题求助

Hey there, let's work through those two errors you're hitting with PrimeNG's Sidebar component in your Angular 4 project.

First, let's break down what's going on:

• The Cannot find module '@angular/core' error is likely a side effect of the metadata mismatch issue.
• The Metadata version mismatch (found version 4, expected 3) is the root problem here—this happens when the TypeScript version you're using doesn't align with what PrimeNG 4.2.1 expects, causing Angular's compiler to misinterpret the component's metadata.

Here's how to fix this step by step: #

1. Adjust your TypeScript version
   Angular 4.3.4 works best with TypeScript versions between 2.3.0 and 2.4.2. Your current typescript: ~2.1.0 is too old, which is triggering the metadata mismatch. Update your package.json to use a compatible version:

   "devDependencies": {
     // ... other dependencies
     "typescript": "~2.3.4"
   }
   

2. Lock PrimeNG to the exact 4.2.1 version
   Using ^4.2.1 might pull in minor updates that could still cause issues. Change it to a fixed version:

   "dependencies": {
     // ... other dependencies
     "primeng": "4.2.1"
   }
   

3. Clean your dependencies and reinstall
   Corrupted node_modules or cache can also cause these odd errors. Run these commands in your project root:

   • Delete the node_modules folder manually, or run:

     rm -rf node_modules
     

   • Delete the package-lock.json file:

     rm package-lock.json
     

   • Clear npm's cache:

     npm cache clean --force
     

   • Reinstall all dependencies:

     npm install
     

4. Verify your AppModule setup
   Your current module.ts looks correct, but double-check that you've imported all required modules:

   import { BrowserModule } from '@angular/platform-browser';
   import { NgModule } from '@angular/core';
   import { SidebarModule } from 'primeng/sidebar';
   import { BrowserAnimationsModule } from '@angular/platform-browser/animations';
   import { AppComponent } from './app.component';
   
   @NgModule({
     declarations: [
       AppComponent
     ],
     imports: [
       BrowserModule,
       SidebarModule,
       BrowserAnimationsModule
     ],
     providers: [],
     bootstrap: [AppComponent]
   })
   export class AppModule { }
   

Why this works: #

The metadata version mismatch occurs because older TypeScript versions (like 2.1.0) generate metadata with version 3, while PrimeNG 4.2.1 is built with a newer TypeScript version that produces metadata version 4. Updating TypeScript to a version compatible with both Angular 4.3.4 and PrimeNG 4.2.1 resolves this conflict, and cleaning your dependencies ensures you're not using cached or corrupted files.

内容的提问来源于stack exchange，提问作者infodev