Angular 错误：类型'；{firstName:string；lastName:string；age:number；.'；不能用作索引类型

我正在尝试将用户列表添加到数组中，它在其中抛出上述错误

export interface User{
    firstName:string;
    lastName:string;
    age:number;
    address:{
        street:string,
        city:string,
        state:string
    }
}

这是我的界面

在这里，我试图添加user[]类型的用户

import { Component, OnInit } from '@angular/core';
import { User } from '../../models/User';

@Component({
  selector: 'app-users',
  templateUrl: './users.component.html',
  styleUrls: ['./users.component.css']
})

export class UsersComponent implements OnInit {

  //Properties
  users :User[];

  //Methods
  constructor() { }

  ngOnInit() {
   this.users[
    {
      firstName: "John",
      lastName: "Doe",
      age: 30,
      address : {
        street: "3rd Cross",
        city: "Bangalore",
        state: "Karnataka"
      }
    }
   ];

  }

}

谁能解释一下我在哪里出错了吗。 代码应为-

ngOnInit() {
   this.users = [
    {
      firstName: "John",
      lastName: "Doe",
      age: 30,
      address : {
        street: "3rd Cross",
        city: "Bangalore",
        state: "Karnataka"
      }
    }
   ];

  }

正如错误中所解释的，您没有将值设置为变量。相反，您试图将值添加为格式错误的数组的索引