ngclass angular

//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'"

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