如何在Angular12中限制搜索结果

<input type="text" [(ngModel)]="searchKeyword" placeholder="输入搜索关键字">
<ul>
  <li *ngFor="let item of filteredItems">{{ item }}</li>
</ul>

import { Component } from '@angular/core';

@Component({
  selector: 'app-search',
  templateUrl: './search.component.html',
  styleUrls: ['./search.component.css']
})
export class SearchComponent {
  items: string[] = ['item1', 'item2', 'item3', 'item4']; // 数据源
  searchKeyword: string = ''; // 搜索关键字
  filteredItems: string[] = []; // 过滤后的结果

  filterItems() {
    this.filteredItems = this.items.filter(item =>
      item.toLowerCase().includes(this.searchKeyword.toLowerCase())
    );
  }
}