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angular nested if else

<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>

nested condition in *ngIf in angular

<ng-container *ngIf="(value1 || value2); else showDefault">
    <ng-container *ngIf="value3!=null && value4==null; else showValue4">
    </ng-container>
    <ng-template #showValue4>
    </ng-template>
</ng-container>
<ng-template #showDefault>
</ng-template>