Answers for "if else in Angular 7"

ng if else

<div *ngIf="condition; else elseBlock">Content to render when condition is true.</div>
<ng-template #elseBlock>Content to render when condition is false.</ng-template>

if angular

<div *ngIf="condition">Content to render when condition is true.</div>

ng else if

<ng-container *ngIf="isDone; else elseNotDone">
      It's Done!
    </ng-container>

    <ng-template #elseNotDone>
      It's Not Done!
    </ng-template>