如何使用 angular 关闭引导模式

问：

我有一个引导 5 模式，我正在尝试从打字稿中关闭它。当我调用函数关闭它时。我收到一个错误，说 unfined 当 dismiss 函数 被称为。

import {NgbModal, ModalDismissReasons,NgbModalRef } from '@ng-bootstrap/ng-bootstrap';
import { ModalSizes } from 'src/app/core/utilities/modal-sizes';
import { timer } from 'rxjs';
declare var window: any;

export class UploadComponent {
 
 @ViewChild("spinnerLoaderModal") content;
  loading = false;
  spinnerDuration = 2000;
  closeResult: string;
  //modalReference: NgbModalRef;
  modalReference: NgbModalRef;
 
 constructor(
   private cdRef: ChangeDetectorRef,
   private modalService: NgbModal,){}


   //this.modalService.open(this.content, ModalSizes.lg);
   
 open(content){
    this.modalReference = this.modalService.open(content);
    this.modalReference.result.then((result) => {
      this.closeResult = `Closed with: ${result}`;
    }, (reason) => {
      this.closeResult = `Dismissed `;
    });
    //this.modalReference.close();
    }

 public closeSpinnerModal()
 {

  this.modalReference.dismiss(); 
 }
 
 public onSubmit(event : MouseEvent) {
 this.isLoading = true;
   this.open(this.content)
   timer(this.spinnerDuration).subscribe(this.closeSpinnerModal)
 }

}

[HTML全文]

<ng-template #spinnerLoaderModal let-c="close" let-d="dismiss">
<div class="modal-body">
      <div class="row">
        <input type="hidden" id="spinLoader" class="form-control">
       </div>
            <img src="../../../../assets/images/loaderBlue.gif" id="bg" alt="" style="width:30%; margin-left: 0; margin-right: 0;">
  </div>
</ng-template>