如何在angular 7中选中和取消选中所有复选框

<div *ngFor="let item of items">
  <input type="checkbox" [(ngModel)]="item.selected">
  {{ item.name }}
</div>

export class YourComponent {
  items: any[] = [
    { name: 'Item 1', selected: false },
    { name: 'Item 2', selected: false },
    { name: 'Item 3', selected: false },
    // ...
  ];
}

export class YourComponent {
  // ...

  selectAll() {
    this.items.forEach(item => item.selected = true);
  }

  deselectAll() {
    this.items.forEach(item => item.selected = false);
  }
}

<button (click)="selectAll()">全选</button>
<button (click)="deselectAll()">取消全选</button>