Angular之特性模块 ( Feature Module )

项目结构

一 创建特性模块，及其包含的组件、服务。

ng g module art
ng g component art/music
ng g component art/dance
ng g service art/performance

二 特性模块

art.module.ts

import { NgModule } from '@angular/core';
import { CommonModule } from '@angular/common';
import { MusicComponent } from './music/music.component';
import { DanceComponent } from './dance/dance.component';
import { PerformanceService } from './performance.service';
 
@NgModule({
  imports: [
    CommonModule
  ],
  // 把特性模块和组件关联起来：添加专属于这个模块的可声明对象（组件、指令和管道）
  declarations: [MusicComponent, DanceComponent],
  // 导出组件：导入特性模块后，就可以使用其中包含的组件模版了
  exports: [
    MusicComponent,
    DanceComponent
  ],
  providers: [
    PerformanceService
  ]
})
export class ArtModule { }

三 组件

music.component.ts

import { Component, OnInit, Input } from '@angular/core';
 
@Component({
  selector: 'app-music',
  templateUrl: './music.component.html',
  styleUrls: ['./music.component.css']
})
export class MusicComponent implements OnInit {
 
  @Input()
  name: string;
 
  constructor() { }
 
  ngOnInit() {
  }
 
}

music.component.html

<p>
  music works!{{name}}
</p>

dance.component.ts

import { Component, OnInit, Input } from '@angular/core';
 
@Component({
  selector: 'app-dance',
  templateUrl: './dance.component.html',
  styleUrls: ['./dance.component.css']
})
export class DanceComponent implements OnInit {
 
  @Input()
  name: string;
 
  constructor() { }
 
  ngOnInit() {
  }
 
}

dance.component.html

<p>
  dance works!{{name}}
</p>

四 服务

performance.service.ts

import { Injectable } from '@angular/core';
 
@Injectable()
export class PerformanceService {
 
  constructor() { }
 
  perform(): string[] {
    return ['唱歌', '跳舞'];
  }
}

五 导入特性模块

app.module.ts

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

六 使用特性模块的组件、服务

app.component.ts

import { Component } from '@angular/core';
import { PerformanceService } from './art/performance.service';
 
@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']
})
export class AppComponent {
 
  constructor(public performance: PerformanceService) {
 
  }
  perform() {
    console.log(this.performance.perform());
  }
}

app.component.html

<p>
  app works!
</p>
<!-- 单向绑定：组件的属性 -->
<app-music [name]="'水边的阿狄丽娜'"></app-music>
<!-- 单向绑定：值是固定的，故使用一次性绑定 ( a "one-time" binding ) -->
<app-dance name="踢踏舞"></app-dance>
<button type="button" (click)="perform();">演出</button>

七 运行效果