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'"
