内置对象

ECMAScript的内置对象

let num: Number = new Number(18);
let date: Date = new Date();
let regExp: RegExp = new RegExp("abc");
let error: Error = new Error("An error occurred");
let xhr: XMLHttpRequest = new XMLHttpRequest();

DOM的内置对象

let div: HTMLElement | null = document.querySelector("div");
let input: HTMLInputElement | null = document.querySelector("input");

let a: NodeList = document.querySelectorAll("a");

let el: NodeListOf<HTMLDivElement | HTMLElement> =
  document.querySelectorAll("div");

BOM的内置对象

let local: Storage = localStorage;
let cookies: Storage = document.cookie as unknown as Storage;