Angular 2服务，如何从Web API下载excel

import { HttpClientModule } from '@angular/common/http';

@NgModule({
  imports: [
    HttpClientModule
  ],
  ...
})
export class AppModule { }

import { HttpClient } from '@angular/common/http';
import { Observable } from 'rxjs';

export class YourService {
  constructor(private http: HttpClient) { }

  downloadExcel(): Observable<Blob> {
    return this.http.get('your-web-api-url', { responseType: 'blob' });
  }
}

export class YourComponent {
  constructor(private yourService: YourService) { }

  download() {
    this.yourService.downloadExcel().subscribe((data: Blob) => {
      const url = window.URL.createObjectURL(data);
      const link = document.createElement('a');
      link.href = url;
      link.download = 'filename.xlsx';
      link.click();
      window.URL.revokeObjectURL(url);
    });
  }
}