angular2無法解決所有參數AppComponent：（？）

Question

import { NgModule } from '@angular/core'; 
import { BrowserModule } from '@angular/platform-browser'; 
import { RestfulComponent } from '/app/rest/app.restful.component.ts'; 
import { HttpModule } from '@angular/http'; 

@NgModule({ 
    imports: [ 
    BrowserModule, 
    HttpModule 
    ], 
    declarations: [ 
    RestfulComponent 
    ], 
    bootstrap: [ RestfulComponent ] 
}) 
export class AppModule { } 

app.restful.module.ts

import { Component } from '@angular/core'; 
import { RestfulService } from '/app/rest/restful/restfull.service.ts'; 

import {Http} from '@angular/http'; 
import { Observable } from 'rxjs'; 


@Component({ 
    selector: 'my-app', 
    template: ` 
    <button (click)="onTestGet()">GET TEST</button><br> 
    <p>Output: {{getData}}</p> 
    `, 
    providers: [RestfulService] 
}) 
export class RestfulComponent { 

    getData: string; 
    postData: string; 
// 
    constructor (private _http: Http){} 

     onTestGet(){ 
      this._restfulService.getCurrentTime().subscribe(
      data => this.getData = JSON.stringify(data), 
      error => alert(error), 
     () => console.log("end") 
      ); 
      } 
} 

app.restful.component.ts

import {Injectable} from '@angular/core'; 
import {Http} from '@angular/http'; 
import {Headers} from '@angular/http'; 
import 'rxjs/add/operator/map' 

@Injectable() 
export class RestfulService { 
     constructor (private _http: Http){} 

     getCurrentTime(){ 
      return this._http.get('http://date.jsontest.com').map(res => res.json()); 
     } 
} 

restful.service.ts

[的test.html2

我沒有關於角多少知識。如果您在缺少任何信息或文件的情況下，我在這裏添加。

我會把他們產生下面的錯誤改變的代碼：

，我應該怎麼辦？構造方法內

Answer 1

DECLARE RestfulService：

constructor(private _restfulService: RestfulService) { }