Leonel Elimpe
by Leonel Elimpe
~1 min read

Tags

  • Angular
  • *ngFor

Angular’s NgForOf provides exported values that can be aliased to local variables. Until today, I’ve only been aware of the index exported value, turns out there’s a couple more.

Four of them in particular are very applicable in my day-to-day usage of Angular: first, last, even, and odd.

  • first

first, a boolean value, is true when the item is the first item in the iterable.

  • last

last, a boolean value, is true when the item is the last item in the iterable.

  • even

even, a boolean value, is true when the item has an even index in the iterable.

  • odd

odd, a boolean value, is true when the item has an odd index in the iterable.

Not leaving out index, a number representing the index of the current item in the iterable.

Here’s a usage example in which we alias the above five exported values to local variables:

<li *ngFor="let user of users; index as i; first as isFirst; last as isLast; even as isEven; odd as isOdd">
   <span *ngIf="isFirst">default</span>
</li>

And that’s it 🙂, hope this is useful to you in some way.