Where should I use Safe Navigation (Elvis Operator, the "?") in Angular?

Question

We undoubtedly use safe navigation in string interpolation ({{}}) to safely navigate values in a nested object with checking nulls or undefined. I have a question that, is it okay to use safe navigation also for:

1. ngIf
2. ngFor
3. ngModel
4. ngClass
5. and other html property bindings like [disabled], [style], etc.

For which scenarios should I use and not?

Answer 1

We can use ? in every place you have mentioned, except two way binding ngModel. You could use when you are using [ngModel] but not when using [(ngModel)]