Angular2 *ngIf check object array length in template

Question

Refered to https://angular.io/docs/ts/latest/guide/displaying-data.html and stack How to check empty object in angular 2 template using *ngIf still getting syntax error self

Answer 1

This article helped me alot figuring out why it wasn't working for me either. It give me a lesson to think of the webpage loading and how angular 2 interacts as a timeline and not just the point in time i'm thinking of. I didn't see anyone else mention this point, so I will...

The reason the *ngIf is needed because it will try to check the length of that variable before the rest of the OnInit stuff happens, and throw the "length undefined" error. So thats why you add the ? because it won't exist yet, but it will soon.