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Can't bind to 'ngIf' since it isn't a known property of 'div' [duplicate]（3个答案）
21天前关闭。
我只想在符合规则的情况下呈现该列，但它不识别我。
Angular

HTML
<div class="middlePoint">
    <ion-row>
      <ion-col class="col-12 text-center titles mt-5"> Ingresa tu PIN </ion-col>
      <ion-col class="col-12 mt-2">
        <ul class="pinCircle">
          <li [class]="mePin.length > 0 ? 'active' : ''"></li>
          <li [class]="mePin.length > 1 ? 'active' : ''"></li>
          <li [class]="mePin.length > 2 ? 'active' : ''"></li>
          <li [class]="mePin.length > 3 ? 'active' : ''"></li>
        </ul>
      </ion-col>
      <ion-col class="mt- 2" size="12" *ngIf="messageError.length > 0">
        <h3 class="text-center color-white">{{ messageError }}</h3>
      </ion-col>
      <ion-col size="12" class="my-loading" *ngIf="loading === true">
        <ion-spinner name="dots"></ion-spinner>
      </ion-col>
    </ion-row>
</div>

COMPONENT.TS
    
@Component({
  selector: "app-pin",
  templateUrl: "./pin.component.html",
  styleUrls: ["./pin.component.scss"],
})
export class PinComponent implements OnInit {
  public messageError: string = "";
  public loading: boolean = true;
  public circlePin: any = 0;
  public mePin: any = "";

我只想在符合规则的情况下呈现该列，但它不识别我。