TYPESCRIPT

add class to element angular in ts

type one

[class.my-class]="step === 'step1'"
type two

[ngClass]="{'my-class': step === 'step1'}"
and multiple option:

[ngClass]="{'my-class': step === 'step1', 'my-class2':step === 'step2' }"
type three

[ngClass]="{1:'my-class1',2:'my-class2',3:'my-class4'}[step]"
type four

[ngClass]="(step=='step1')?'my-class1':'my-class2'"

angualr add class to component

@Component({
   selector: 'app-your-component',
   templateUrl: './your-component.component.html',,
   host: {'class': 'your-class'}
})
export class YourComponent implements OnInit {
...
}

add class based on value in angularjs

<tr ng-repeat="scores in Test" ng-class="{true: 'warning', false: 'ok'}[scores.Indicator == 'Negative']">                       
     <td>Overall: {{ scores.Indicator }}</td>
</tr>