问是否有一种方法来获取存储在消防局中的数组中的对象的索引？

EN

<ion-card class="lightCard" *ngFor="let reviews of revArr" (click)="selectReview()">

        <ion-card-header>
          <ion-grid>
            <ion-row>
              <ion-icon name="person-circle-sharp" class="profIcon"></ion-icon>
              <!-- <ion-card-subtitle>Card Subtitle</ion-card-subtitle> -->
              <ion-card-title class="cardUsername fontWhite" style="font-size: 35px;">{{reviews.userName}}</ion-card-title>
            </ion-row>
          </ion-grid>
          
        </ion-card-header>
          
        <ion-card-content class="font cardContent">
          <h1 class="title" style="font-weight: bold;">{{reviews.title}}</h1>
          {{reviews.review}}
        </ion-card-content>
      
      </ion-card>

  ngOnInit() {
    const compId: string = this.route.snapshot.paramMap.get('id'); //get id

     //for reviews array in `reviews`
    this.reviewCollection = this.afStore.doc(`reviews/${compId}`)
    this.rev = this.reviewCollection.valueChanges().subscribe(item =>{
    this.revArr = item.reviews
    this.userNrev = item.reviews.userName
     })   
  }

  async selectReview(){
  
    const actionSheet = await this.actionSheetCtrl.create({
      header: "Delete "+ this.userNrev + "'s review?",
      buttons: [
        {
          text: 'Delete',
          handler: () => {
           //delete code
          }
        }
      ]
    })
    await actionSheet.present();
  }