bersarang sudut jika lain
<ng-container *ngIf="condition_01; then then_01; else else_01"></ng-container>
<ng-template #then_01>
<ng-container *ngIf="condition_02; then then_02; else else_02"></ng-container>
<ng-template #then_02>
<div>Then 02 block content</div>
</ng-template>
<ng-template #else_02>
<div>Else 02 block content</div>
</ng-template>
</ng-template>
<ng-template #else_01>
<div>Else 01 block content</div>
</ng-template>
amit.bhagat