NgIf, Else, and Then

- [Instructor] One of the most basic elements…of programming is the if else statement and, surprisingly,…up until version four Angular did not support else.…Fortunately, now it does.…If, else, and then are all defined…within the ngIf directive.…We define ngIf inside of an HTML element…and inside of the quotes we bind it…to a template expression.…When we add else, we're able…to define a local template variable and, when we add them,…we can define a local template variable…based on the template expression resulting in true or false.…

So let's give it a try in our own project.…We currently have a title property on line 16.…Let's add an if statement and an h1 tag.…So let's go ahead and remove all of our HTML to this point.…And let's add an h1 tag…and this is where we add the ngIf directive…so *ngIf="title"…and we'll simply add...…

"I'm here" and we'll save it, go back to our browser,…and, as you can see, the h1 element remains…because the title property is present…in our component class.…Now if we add a not operator on title,…