how to use the behaviorsubject function from the rxjs library in typescript

A BehaviorSubject is a type of RxJS Subject that allows initialization with an initial value and emits its current value (which can be fetched by getValue method) to new subscribers.

Here's an example of how to use the BehaviorSubject function in Typescript:

index.ts
import { BehaviorSubject } from 'rxjs';

// Initialize a new BehaviorSubject with an initial value
const behaviorSubject = new BehaviorSubject<string>("Initial value");

// Subscribe to the BehaviorSubject and log its current value
behaviorSubject.subscribe(value => console.log(`The current value is ${value}`));

// Update the value of the BehaviorSubject
behaviorSubject.next("New value");
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In the example above, we first import the BehaviorSubject function from the rxjs library. We then create a new instance of the BehaviorSubject with an initial value of "Initial value". Next, we subscribe to the BehaviorSubject and log its current value (which is "Initial value") using the subscribe method. Finally, we update the value of the BehaviorSubject using the next method with the argument "New value", which will trigger the BehaviorSubject to emit this new value and all its subscribers will receive the updated value.