xxxxxxxxxx
<a [ngClass]="{'class1':array.status === 'active','class2':array.status === 'idle','class3':array.status === 'inactive',}">
xxxxxxxxxx
<section [ngClass]="{'class1':condition1, 'class2': condition2, 'class3':condition3}" >
xxxxxxxxxx
[ngClass]="[ mainIMG.touched && !mainIMG.valid?
'class1 class2':
'class3 class2' ]"