文档针对以下项目环境,借助webpack实现angular路由懒加载:
- Jhipster 4.x
- Anguar 2~5
- Jhipster 5(生成项目时,admin module已实现异步路由的配置)
- 基于webpack配置
开始正文:
1.安装依赖
npm install angular-router-loader --save-dev
2.添加loader
添加安装的依赖到 loader
// webpack.common.js
module: {
rules: [
{
test: /\.ts$/,
loaders: [
'angular2-template-loader',
'awesome-typescript-loader',
'angular-router-loader' // loader
],
...
3.创建(或改造)异步路由模块
如创建Customer模块
Customer 模块不会被立即加载,直到用户路由到Customer页。这个模块有自己的组件和路由配置,加载的入口是customer.module.ts,代码如下:
// customer.module.ts
import { NgModule } from '@angular/core';
import { CommonModule } from '@angular/common';
import { CustomerRoutingModule } from './customer-routing.module';
import { CustomerComponent } from './customer.component';
@NgModule({
imports: [
CommonModule,
CustomerRoutingModule
],
declarations: [CustomerComponent]
})
export class CustomerModule { }
// customer-routing.module.ts
/*
* customer.component.ts 和 customer.component.html等亦可使用ng命令创建
*/
import { CustomerComponent } from './customer.component';
import { NgModule } from '@angular/core';
import { Routes, RouterModule } from '@angular/router';
const routes: Routes = [
{
path: '',
component: CustomerComponent
}
];
@NgModule({
imports: [RouterModule.forChild(routes)],
exports: [RouterModule]
})
export class CustomerRoutingModule { }
4.配置Angular路由
配置路由文件 Jhipster项目中可能是 layout-routing.module.ts (ng 生成的可能是 app-routing.module.ts)
路由配置方案1
import { LocalComponent } from './local/local.component';
import { NgModule } from '@angular/core';
import { Routes, RouterModule } from '@angular/router';
const routes: Routes = [
{
path: 'customer',
loadChildren: '../customer/customer.module#CustomerModule' // 异步路由加载模块,注:路径必须正确
},
{
path: 'local', // 非异步路由
component: LocalComponent
}
];
@NgModule({
imports: [RouterModule.forRoot(routes, { useHash: true })],
exports: [RouterModule]
})
export class AppRoutingModule { }
路由配置方案2
在我的项目中曾经使用这种方式进行异步路由的配置,发现可能存在数据请求事件的问题。项目中遇到的场景是:把模块改造完成后,能正常异步加载路由,但由于业务复杂,加载业页时部分请求会重复(即首页请求了A,异步路由加载后会再次请求A),然而这部分请求没有被再次执行。因此使用下面的另一种方案进行异步路由配置。
import { LocalComponent } from './local/local.component';
import { NgModule } from '@angular/core';
import { Routes, RouterModule } from '@angular/router';
const routes: Routes = [
{
// 异步路由加载模块,注:路径必须正确
path: 'customer', loadChildren: () => new Promise((resolve) => {
(require as any).ensure([], (require) => {
resolve(require('../customer/customer.module').CustomerModule);
});
})
},
{
path: 'local', // 非异步路由
component: LocalComponent
}
];
@NgModule({
imports: [RouterModule.forRoot(routes, { useHash: true })],
exports: [RouterModule]
})
export class AppRoutingModule { }
5.配置module
配置 Angular app.module.ts
import { FormsModule } from '@angular/forms';
import { BrowserAnimationsModule } from '@angular/platform-browser/animations';
import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { AppRoutingModule } from './app-routing.module';
import { AppComponent } from './app.component';
import { LocalComponent } from './local/local.component';
@NgModule({
declarations: [
AppComponent,
LocalComponent // 非异步路由组件
],
imports: [
BrowserModule,
BrowserAnimationsModule,
FormsModule,
AppRoutingModule // 异步路由模块
],
providers: [],
bootstrap: [AppComponent]
})
export class AppModule { }
6.构建并运行
yarn start
或 npm run start
运行后,会编译出模块文件,当跳转到异步路由时,查看网络请求,即可看到跳转路由时会加载对应的js文件。如下图