class true and false in angular8 code example

Example 1: ngclass multiple conditions

<a [ngClass]="{'class1':array.status === 'active','class2':array.status === 'idle','class3':array.status === 'inactive',}">

Example 2: conditionally assign a css class angular 9

<div [ngClass]="{'message': info.priority < 10,
                 'warn': info.priority > 10 && info.priority < 20, 
                 'error': info.priority > 30}">

{{info.text}}

</div>