Angular如何在没有NgModel的情况下默认选中单选按钮

<input type="radio" id="option1" [checked]="isChecked">
<label for="option1">Option 1</label>
<input type="radio" id="option2">
<label for="option2">Option 2</label>

import { Component, ViewChild, AfterViewInit } from '@angular/core';

@Component({
  selector: 'app-example',
  templateUrl: './example.component.html',
  styleUrls: ['./example.component.css']
})
export class ExampleComponent implements AfterViewInit {
  isChecked: boolean = true;

  @ViewChild('option1') option1: any;

  ngAfterViewInit() {
    this.option1.nativeElement.checked = this.isChecked;
  }
}