<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>

<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>

​