angular 6获取文件上次修改的时间戳？

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

@Component({
  selector: 'app-file-upload',
  templateUrl: './file-upload.component.html',
  styleUrls: ['./file-upload.component.css']
})
export class FileUploadComponent {
  constructor() { }

  onFileChange(event) {
    const file = event.target.files[0];
    const fileReader = new FileReader();

    fileReader.onloadend = (e) => {
      const lastModified = file.lastModified;
      console.log('文件上次修改时间戳：', lastModified);
    };

    fileReader.readAsDataURL(file);
  }
}

<input type="file" (change)="onFileChange($event)">