如何在angular中使用ajax实现搜索？

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

constructor(private http: HttpClient) { }

search(keyword: string): Observable<any> {
  const url = 'http://example.com/api/search?keyword=' + keyword;
  return this.http.get(url);
}

<input type="text" [(ngModel)]="keyword">
<button (click)="search(keyword)">Search</button>

<ul>
  <li *ngFor="let result of searchResults">{{ result }}</li>
</ul>

keyword: string;
searchResults: any[];

search(keyword: string): void {
  this.search(keyword).subscribe(results => {
    this.searchResults = results;
  });
}