Angular 8 中单页应用程序上的跨组件通信

Question

我正在开发单页应用程序，前端使用 Angular 8，后端使用 Laravel。从登录表单捕获数据然后通过 JWT 提交到后端后工作正常。后来我得到回应在后端表单 (login.component.ts) 的逻辑文件上。

现在我正在尝试通过名为 AuthCheck.Finally 的共享服务将登录组件的响应传递到另一个组件，我将数据传递到 Navbar 组件文件并最终将其显示在视图上。基本上是跨组件通信。

在服务中我使用 rxjs 来监听响应并设置一个 observable.Next 我试图将我的数据分配给服务中的一个变量，我在 Navbar 组件逻辑文件中监听并显示在导航栏视图..

问题是我不断收到 ERROR TypeError: "this.AuthCheck.checkUser is not a function" 的错误，这是从登录组件

抛出的

~请帮忙？

Login.component.ts

import { Component, OnInit } from '@angular/core';
import { AuthService } from 'src/app/Services/auth.service';
import { TokenService } from 'src/app/Services/token.service';
import { Router } from '@angular/router';
import { AuthCheckService } from 'src/app/Services/auth-check.service';

@Component({
  selector: 'app-login',
  templateUrl: './login.component.html',
  styleUrls: ['./login.component.css']
})
export class LoginComponent implements OnInit {

  public form = {
    email: null,
    password: null
  };

  public error = null;

  constructor(
    private Auth:AuthService,
    private Token:TokenService,
    private router: Router,
    private AuthCheck : AuthCheckService
  ) { }

  //Submit the form data to the backend
  onSubmit(){
    this.Auth.login(this.form).subscribe(
      data => this.handleResponse(data),
      error => this.handleError(error)
    );
  }

  //Function to listen to the response
  handleResponse(data){
    //Pass the data to checkUser method in AuthCheckService
    this.AuthCheck.checkUser(data.user);
  }

  //Handles any errors
  handleError(error){
      this.error = error.error.error;
  }

  ngOnInit() {
  }

}

AuthCheck 服务

import { Injectable } from '@angular/core';
import { BehaviorSubject } from 'rxjs';

@Injectable({
  providedIn: 'root'
})
export class AuthCheckService {

private userName = null;

    private userName = new BehaviorSubject<string>(this.checkUser());
    checkUser$ = this.userName.asObservable();

    checkUser(data: any){
        this.user = data;
        this.userName.next(this.user);
    }

    constructor() { }
}

导航栏组件ts文件

import { Component, OnInit } from '@angular/core';
import { AuthCheckService } from 'src/app/Services/auth-check.service';

@Component({
  selector: 'app-navbar',
  templateUrl: './navbar.component.html',
  styleUrls: ['./navbar.component.css']
})
export class NavbarComponent implements OnInit {

  public userName : string;

  constructor(
    private AuthCheck : AuthCheckService
  ) { }

  ngOnInit() {
      this.AuthCheck.checkUser$.subscribe(message => this.userName = message);
  }
}

导航栏组件（标记文件）

<a class="navbar-brand" *ngIf="loggedIn">Welcome {{ userName }}</a>

Answer 1

您创建了一个属性和一个同名 (checkUser) 的方法，将其更改如下：

将 checkUser 更改为 checkUser$。您还应该将 BehaviorSubject 设置为 userName。请取消注释行

AuthCheck 服务

//private userName = null;

//Check logged in userName
private userName = new BehaviorSubject<string>('Martin');
checkUser$ = this.userName.asObservable();


checkUser(data: any){
    this.user = data;
    this.userName.next(this.user);
}

在您的导航栏组件中

ngOnInit() {
   this.AuthCheck.checkUser$.subscribe(message => this.userName = message);
}

Angular 8 中单页应用程序上的跨组件通信

Cross-Component communication on a Single Page Application in Angular 8

angular

components

single-page-application

communication