位于索引处的数组返回undefined in Angular ngAfterViewInit

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

@Component({
  selector: 'app-example',
  template: `
    <div #myDiv></div>
  `,
})
export class ExampleComponent implements AfterViewInit {
  @ViewChild('myDiv') myDiv: ElementRef;

  ngAfterViewInit() {
    // 在ngAfterViewInit中访问数组元素
    const myArray = [1, 2, 3];
    const index = 3;
    const element = myArray[index];

    if (element === undefined) {
      console.log('数组索引超出范围');
    } else {
      console.log('数组元素:', element);
    }

    // 在ngAfterViewInit中访问DOM元素
    if (this.myDiv.nativeElement === undefined) {
      console.log('无法获取DOM元素');
    } else {
      console.log('DOM元素:', this.myDiv.nativeElement);
    }
  }
}