Function setLanguageCode

setLanguageCode(
auth: FirebaseAuthTypes.Module,
languageCode: string | null,
): Promise<void>
Sets the language code.

Example
```
// Set language to French
await firebase.auth().setLanguageCode('fr');
```
Parameters
- auth: FirebaseAuthTypes.Module
  The Auth instance.
- languageCode: string | null
  An ISO language code. 'null' value will set the language code to the app's current language.
Returns Promise<void>
- Defined in auth/lib/modular/index.d.ts:419