Lazy loading in Angular2 RC7 and angular-cli webpa

2019-01-19 17:14发布

问题:

I have created a new app using ng new but when I try to configure a module to load using lazy loading I keep getting an error that the module cannot be found.

EXCEPTION: Uncaught (in promise): Error: Cannot find module 'app/home/home.module'

package.json

"dependencies": {
    "@angular/common": "2.0.0-rc.7",
    "@angular/compiler": "2.0.0-rc.7",
    "@angular/core": "2.0.0-rc.7",
    "@angular/forms": "2.0.0-rc.7",
    "@angular/http": "2.0.0-rc.7",
    "@angular/platform-browser": "2.0.0-rc.7",
    "@angular/platform-browser-dynamic": "2.0.0-rc.7",
    "@angular/router": "3.0.0-rc.3",
    "core-js": "^2.4.1",
    "rxjs": "5.0.0-beta.12",
    "ts-helpers": "^1.1.1",
    "zone.js": "^0.6.21"
  },
  "devDependencies": {
    "@types/jasmine": "^2.2.30",
    "angular-cli": "1.0.0-beta.11-webpack.9-4",
    "codelyzer": "~0.0.26",
    "jasmine-core": "2.4.1",
    "jasmine-spec-reporter": "2.5.0",
    "karma": "1.2.0",
    "karma-chrome-launcher": "^2.0.0",
    "karma-cli": "^1.0.1",
    "karma-jasmine": "^1.0.2",
    "karma-remap-istanbul": "^0.2.1",
    "protractor": "4.0.5",
    "ts-node": "1.2.1",
    "tslint": "3.13.0",
    "typescript": "2.0.2"
  }
  • angular2 RC7
  • angular-cli: 1.0.0-beta.11-webpack.9-4
  • node: 6.5.0
  • os: win32 x64

app.routing.ts:

import { ModuleWithProviders } from '@angular/core';
import { Routes, RouterModule } from '@angular/router';

const appRoutes: Routes = [{
    path: '',
    redirectTo: 'home',
    pathMatch: 'full'
},
{
    path: `home`,
    loadChildren: `app/home/home.module`
}];
export const routing: ModuleWithProviders = RouterModule.forRoot(appRoutes);

app.module.ts

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { FormsModule } from '@angular/forms';
import { HttpModule } from '@angular/http';

import { AppComponent } from './app.component';

import { routing } from './app.routing';

@NgModule({
  declarations: [
     AppComponent
  ],
  imports: [
    BrowserModule,
    FormsModule,
    HttpModule,
    routing
  ],
  providers: [],
  bootstrap: [AppComponent]
})
export class AppModule { }

app.component.ts

import { Component } from '@angular/core';

@Component({
  selector: 'app-root',
  templateUrl: 'app.component.html',
  styleUrls: ['app.component.css']
})
export class AppComponent {
  title = 'app works!';
}

app.component.html

<router-outlet></router-outlet>

I'm sure I'm missing something stupid but I tried various options and nothing has worked so far. Given my configuration, am I missing anything?

Thanks in advance, Stephen

回答1:

With RC7, you can do as follow:

const appRoutes: Routes = [
  {
    path: 'home',
    loadChildren: 'app/home/home.module#HomeModule',
  }
];

Don't forget the "#"

Then kill ng serve and restart it

It will works with angular-cli@webpack

P.S: The angular convention is to prefix lazy loaded folders with a (+) e.g. +home/



回答2:

The problem is not present in RC7 anymore.

{path:"lazy", loadChildren: 'app/path/to/module#Class'}

will work.


The mechanism you are using is still systemjs based. I couldn't make it work with webpack using the "path#class" syntax. So we require the module directly:

First we'll need the es6-promise-loader:

npm i --save-dev es6-promise-loader

Then define your route like this:

{path:"lazy", loadChildren: () => require('es6-promise!./path/to/module')('ClassName')}

the es6-promise-loader replaces the above with this:

loadChildren: () => new Promise(function (resolve) {
        require.ensure([], function (require) {
          resolve(require('./path/to/module')['ClassName']));
        });
      });

which is the proper way to load a module with webpack, but cumbersome to put into every route.