Check out example codes for "ng if else". It will help you in understanding the concepts better.
Code Example 1
<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>
Code Example 2
<div *ngIf="isLoggedIn; else loggedOut">
Welcome back, friend.
</div>
<ng-template #loggedOut>
Please friend, login.
</ng-template>
Code Example 3
content_copy
<div *ngIf="condition; then thenBlock else elseBlock"></div>
<ng-template #thenBlock>Content to render when condition is true.</ng-template>
<ng-template #elseBlock>Content to render when condition is false.</ng-template>
Code Example 4
<ng-container
*ngIf="isLoggedIn; then loggedIn; else loggedOut">
</ng-container>
<ng-template #loggedIn>
<div>
Welcome back, friend.
</div>
</ng-template>
<ng-template #loggedOut>
<div>
Please friend, login.
</div>
</ng-template>
Code Example 5
<div *ngIf="condition">
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