Home > @firebase/auth > onAuthStateChanged
onAuthStateChanged() function
Adds an observer for changes to the user's sign-in state.
Signature:
export declare function onAuthStateChanged(auth: Auth, nextOrObserver: NextOrObserver<User>, error?: ErrorFn, completed?: CompleteFn): Unsubscribe;
Parameters
| Parameter | Type | Description |
|---|---|---|
| auth | Auth | The Auth instance. |
| nextOrObserver | NextOrObserver<User> | callback triggered on change. |
| error | ErrorFn | callback triggered on error. |
| completed | CompleteFn | callback triggered when observer is removed. |
Returns:
Unsubscribe
Description
To keep the old behavior, see onIdTokenChanged().