Question

How to change the value of an Observable in TypeScript Angular?

"I’m working on an Angular project, and I’m trying to change the value of an Observable. However, I’m having trouble figuring out how to update or modify the value of the Observable in my component. I know I can subscribe to it, but I’m not sure how to actually change the value the Observable holds or how to emit a new value. Can anyone help me with the right approach to do this in TypeScript with Angular?"

Answer 1

To change the value of an Observable in Angular (TypeScript), you typically use a Subject or BehaviorSubject from rxjs. Here's how:

using Subject:

private mySubject = new Subject<any>();

changeValue(newValue: any) {
  this.mySubject.next(newValue);
}

Using BehaviorSubject:

private myBehaviorSubject = new BehaviorSubject<any>(initialValue);

changeValue(newValue: any) {
  this.myBehaviorSubject.next(newValue);
}

• Use .next() to emit a new value.
• BehaviorSubject holds a current value, while Subject does not.