The properties are not found in the type 'Observable<Todo[]>'

Question

The properties are not found in the type 'Observable<Todo[]>'

I'm currently following a YouTube tutorial and I've hit a roadblock trying to figure out where the error is originating from?

Error Message: Type 'Observable' is missing properties such as length, pop, push, concat, and 25 more.ts(2740)

export class ToDosComponent implements OnInit {

  todos:Todo[];

  constructor(private todoService:TodoService) { }

  ngOnInit(): void {
    this.todos = this.todoService.getTodos();

  }

This refers to the specific class:

import { Injectable } from '@angular/core';
import { Observable } from 'rxjs';
import { HttpClient, HttpHeaders } from '@angular/common/http';

import { Todo } from '../models/Todo';


@Injectable({
  providedIn: 'root'
})
export class TodoService {
  todosUrl = 'https://jsonplaceholder.typicode.com/todos';
  todosLimit = '?_limit=5';

  constructor(private http:HttpClient) { }

  getTodos():Observable<Todo[]>{

    return this.http.get<Todo[]>('${this.todosUrl} $ {this.todosLimit}');

  }

angular typescript

Answer 1

Answer №1

To properly retrieve the data from the getTodos() function and assign it to this.todos, you must subscribe to the observable. Here is an example implementation:

export class ToDosComponent implements OnInit {
  todos: Todo[];

  constructor(private todoService:TodoService) { }

  ngOnInit(): void {
    this.todoService.getTodos().subscribe(
      response => { this.todos = response },
      error => {
        // It's always a good practice to handle errors from HTTP observables
      }
    );
  }
}

It's important to note that Angular HttpClient's get() method returns an observable. This means that if you simply assign it to this.todos, you will be assigning the observable itself rather than the actual response data. By subscribing to the observable, you can access the response data correctly.

Answer 2

To properly retrieve the data from the getTodos() function and assign it to this.todos, you must subscribe to the observable. Here is an example implementation:

export class ToDosComponent implements OnInit {
  todos: Todo[];

  constructor(private todoService:TodoService) { }

  ngOnInit(): void {
    this.todoService.getTodos().subscribe(
      response => { this.todos = response },
      error => {
        // It's always a good practice to handle errors from HTTP observables
      }
    );
  }
}

It's important to note that Angular HttpClient's get() method returns an observable. This means that if you simply assign it to this.todos, you will be assigning the observable itself rather than the actual response data. By subscribing to the observable, you can access the response data correctly.

The properties are not found in the type 'Observable<Todo[]>'

Answer №1

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