angular4-注入服務

//配置已建立的服務:
import { MemberService } from "./member.service";
@NgModule({
  // ...
  providers: [MemberService]
})
export class AppModule { }

//導入已建立的服務
import { MemberService } from '../member.service';

//使用構造注入方式，注入服務
export class MembersComponent implements OnInit {
   // ...
   constructor(private memberService: MemberService) { }
}

建立 MemberService 服務

import { Injectable } from '@angular/core';
import { Http } from '@angular/http';

@Injectable()
export class MemberService {
    constructor(private http: Http) { }

    getMembers() { return this.http .get(`https://api.github.com/orgs/angular/members?page=1&per_page=5`)
            .map(res => res.json()) }
}

使用 MemberService 服務

import { MemberService } from "./member.service";

@Component({...})
export class MembersComponent implements OnInit {
    members: Member[];

    constructor(private memberService: MemberService) { }

    ngOnInit() {
        this.memberService.getMembers()
            .subscribe(data => {
                if (data) this.members = data;
            });
    }
}