///index.html 引入js文件
 class Dialog {
    constructor() {
        this.create();
    }
    create(){
        this.dialog = document.createElement("div");
        this.dialog.style = `
            background: rgba(0, 0, 0, .7);
            width: 100%;
            height: 100%;
            position: fixed;
            left: 0;
            top: 0;
        `
        this.dialog.innerHTML=`
            <input type="text" placeholder="请输入用户名">
            <button>确定</button>
            <button>取消</button>
        `
        document.body.appendChild(this.dialog);
        let btns=this.dialog.querySelectorAll("button"),
            ipt=document.querySelector("input");
        btns[0].onclick=()=>{
            location.href="./qita.html";
            localStorage.setItem("username",ipt.value)
        }
        btns[1].onclick=()=>{
            this.dialog.remove();
        }
    }
}
new Dialog();

//第个2html
//代码
 //标签script
  document.querySelector("body").innerHTML=localStorage.getItem("username")
//script