Angular2 Doing an else with ngClass

Source: https://stackoverflow.com/questions/38203030/angular2-doing-an-else-with-ngclass/38203292

Indeed

<p class="{{condition ? 'checked' : 'unchecked'}}">

or

<p [ngClass]="condition ? 'checked' : 'unchecked'">

or

<p [ngClass]="[condition ? 'checked' : 'unchecked']">