角度4：从不同的组件调用方法

我有2个兄弟组件,我在一个组件中做一个http请求,如果发生特定情况,它应该发出另一个http请求,写在另一个组件中.所以我应该能够在第一个组件中调用该方法.

这是第一个组成部分：

import { Component,OnInit,Inject } from '@angular/core';
import { Http } from '@angular/http';
import { SendCardComponent } from '../send-card/send-card.component';

@Component({
  selector: 'app-input-field',templateUrl: './input-field.component.html',styleUrls: ['./input-field.component.css'],})

export class InputFieldComponent implements OnInit {

value = '';
output = '';
@Inject(SendCardComponent) saro: SendCardComponent;

constructor(private http : Http) { }
onEnter(value: string) { 

this.value = value;


this.http.post('http://localhost:5000/APIconversation/',{"val":value})
  .map(response=>response.json())
  .subscribe(
      data => {

            this.output = data.result.fulfillment.speech,if(data.result.fulfillment.speech == 'test'){
                saro.sendCard('done','1' );   
            }               

       });

 }

我试图从InputFieldComponent调用sendCardComponent中定义的sendCard(),如下所示：

import { Component,OnInit } from '@angular/core';
import { Http } from '@angular/http';

@Component({
  selector: 'app-send-card',templateUrl: './send-card.component.html',styleUrls: ['./send-card.component.css']
})

export class SendCardComponent implements OnInit {

constructor(private http : Http) { }

ngOnInit() {

}

 output = '';

 sendCard(value:string,id:number){
   this.http.post('http://localhost:5000/APIconversation/',{"val":value})
  .map(response=>response.json())
  .subscribe(
      data => {

             this.output = data.result.fulfillment.messages[1].payload.options[id].type = $('#'+(id+1)+'>span').html();  

      });
} //sendCard

}

调用saro.sendCard时出错：

[ts] cannot find name ‘saro’

我究竟做错了什么？

解决方法

在InputFieldComponent中创建SendCardComponent的实例

import { Http } from '@angular/http';
import { SendCardComponent } from '../send-card/send-card.component';

export class InputFieldComponent{

    //your other variables and methods

    constructor(private http : Http) { }

    let saro = new SendCardComponent(this.http);

    saro.sendCard()

}