我对在Angular中传递数据有疑问。
首先,我没有<parent><child [data]=parent.data></child></parent>
我的结构是
<container>
<navbar>
<summary></summary>
<child-summary><child-summary>
</navbar>
<content></content>
</container>
所以,在<summary />
我有一个选择,它会向<child-summary />
和<content />
发送值。
使用<summary />
组件内的(更改)很好地解决了OnSelect方法。
所以,我尝试使用@Input
,@Output
和@EventEmitter
指令,但我没有看到如何将事件检索为组件的@Input,除非继续使用父/儿童模式。我创建的所有例子都有组件之间的关系。
编辑:使用BehaviorSubject不起作用的示例(API的所有连接服务都运行正常,只有在开始时触发了observable,但是当select的值发生了变化时才触发)
shared service = company.service.ts(用于检索公司数据)
import { Injectable } from '@angular/core';
import { Headers, Http, Response } from '@angular/http';
import { BehaviorSubject } from 'rxjs/BehaviorSubject';
import { Observable } from 'rxjs/Observable';
import 'rxjs/add/operator/toPromise';
@Injectable()
export class SrvCompany {
private accountsNumber = new BehaviorSubject<string[]>([]);
currentAccountsNumber = this.accountsNumber.asObservable();
changeMessage(accountsNumber: string[]) {
this.accountsNumber.next(accountsNumber);
}
private _companyUrl = 'api/tiers/';
constructor(private http: Http) { }
getSociete(): Promise<Response> {
let url = this._companyUrl;
return this.http.get(url).toPromise();
}
}
invoice.component.ts(“孩子”)
import { Component, OnInit, Input } from '@angular/core';
import { Headers, Http, Response } from '@angular/http';
import { SrvInvoice } from './invoice.service';
import { SrvCompany } from '../company/company.service';
@Component({
selector: 'invoice',
templateUrl: 'tsScripts/invoice/invoice.html',
providers: [SrvInvoice, SrvCompany]
})
export class InvoiceComponent implements OnInit {
invoice: any;
constructor(private srvInvoice: SrvInvoice, private srvCompany: SrvCompany)
{
}
ngOnInit(): void {
//this.getInvoice("F001");
// Invoice data is linked to accounts number from company.
this.srvCompany.currentAccountsNumber.subscribe(accountsNumber => {
console.log(accountsNumber);
if (accountsNumber.length > 0) {
this.srvInvoice.getInvoice(accountsNumber).then(data => this.invoice = data.json());
}
});
}
//getInvoice(id: any) {
// this.srvInvoice.getInvoice(id).then(data => this.invoice = data.json());
//}
}
company.component.ts(trigerring“parent”)
import { Component, Inject, OnInit, Input } from '@angular/core';
import { Headers, Http, Response } from '@angular/http';
import { SrvCompany } from './company.service';
@Component({
selector: 'company',
templateUrl: 'tsScripts/company/company.html',
providers: [SrvCompany]
})
export class CompanyComponent implements OnInit {
societes: any[];
soc: Response[]; // debug purpose
selectedSociete: any;
ville: any;
ref: any;
cp: any;
accountNumber: any[];
constructor(private srvSociete: SrvCompany)
{
}
ngOnInit(): void {
this.getSocietes();
}
getSocietes(): void {
this.srvSociete.getSociete()
.then(data => this.societes = data.json())
.then(data => this.selectItem(this.societes[0].Id));
}
selectItem(value: any) {
this.selectedSociete = this.societes.filter((item: any) => item.Id === value)[0];
this.cp = this.selectedSociete.CodePostal;
this.ville = this.selectedSociete.Ville;
this.ref = this.selectedSociete.Id;
this.accountNumber = this.selectedSociete.Accounts;
console.log(this.accountNumber);
this.srvSociete.changeMessage(this.accountNumber);
}
}
答案 0 :(得分:68)
这是您希望使用共享服务的情况,因为您的组件是兄弟姐妹和孙子女。以下是视频中的一个示例,我创建了一个关于sharing data between components的视频,可以解决这个问题。
首先在服务中创建一个BehaviorSubject
import { Injectable } from '@angular/core';
import { BehaviorSubject } from 'rxjs/BehaviorSubject';
@Injectable()
export class DataService {
private messageSource = new BehaviorSubject("default message");
currentMessage = this.messageSource.asObservable();
constructor() { }
changeMessage(message: string) {
this.messageSource.next(message)
}
}
然后将此服务注入每个组件并订阅observable。
import { Component, OnInit } from '@angular/core';
import { DataService } from "../data.service";
@Component({
selector: 'app-parent',
template: `
{{message}}
`,
styleUrls: ['./sibling.component.css']
})
export class ParentComponent implements OnInit {
message:string;
constructor(private data: DataService) { }
ngOnInit() {
this.data.currentMessage.subscribe(message => this.message = message)
}
}
您可以更改任一组件的值,即使您没有父/子关系,也会更新该值。
import { Component, OnInit } from '@angular/core';
import { DataService } from "../data.service";
@Component({
selector: 'app-sibling',
template: `
{{message}}
<button (click)="newMessage()">New Message</button>
`,
styleUrls: ['./sibling.component.css']
})
export class SiblingComponent implements OnInit {
message:string;
constructor(private data: DataService) { }
ngOnInit() {
this.data.currentMessage.subscribe(message => this.message = message)
}
newMessage() {
this.data.changeMessage("Hello from Sibling")
}
}
答案 1 :(得分:0)
如果组件不相关,则需要使用服务
https://angular.io/docs/ts/latest/cookbook/component-communication.html#!#bidirectional-service
答案 2 :(得分:0)
有两种解决方案。
这可以通过使用observable的共享服务来完成。
您可以使用ngrx / store进行此操作。这类似于Redux arch。您将从州获取数据。
答案 3 :(得分:0)
这是使用事件发射器和服务在两个独立组件之间共享数据的最简单示例
答案 4 :(得分:0)
当您提到不相关的组件时,我将假定它们没有任何父组件。如果假设不正确,请随时read another of my answers where both cases are addressed。
因此,由于没有共同的父母,我们可以使用可注射服务。在这种情况下,只需将服务注入组件并订阅其事件即可。
(就像下图所示-taken from here-只是我们将服务注入两个组件一样)
文档很好地说明了如何Create and register an injectable service。