I have this error :
error TS2322: Type 'Observable<any[]>' is not assignable to type 'null'.
For this code :
import { Component, OnInit } from '@angular/core';
import {HttpClient} from "@angular/common/http";
@Component({
selector: 'app-articles',
templateUrl: './articles.component.html',
styleUrls: ['./articles.component.css']
})
export class ArticlesComponent implements OnInit {
articles$ = null;
constructor(private httpClient: HttpClient) { }
ngOnInit(): void {
// @ts-ignore
this.articles$ = this.httpClient.get<any[]>('http://localhost:3000/articles');
}
}
I added : // @ts-ignore so it can bypass the error and print me my database content.
But of course it's a temporary solution, i'd like to get rid of this error.
The issue is that you set articles$ = null; which implies its type is null.
To fix the type error you could do something like this
articles$: null | Observable<any[]> = null;
I prefere to do it like this. The ? tells the compile that it might be undefined
articles$?: Observable<any[]>; // type is: undefined | Observable<any[]>
I believe the error is displaying as you have not defined the type of articles$
you can resolve this by just defining the type during the initial declaration like as follows.
articles$:Observable<ArticleModel[]> = null;
Alternatively, you could just remove the initailly assigned null value.