let lisi={ name:"李四" }; let wangwu={ name:"王五" }; function User(web,url){ console.log(web+url+this.name); } //都是立即执行的 User.call(lisi,"hdr","hdr.com"); User.apply(wangwu,["hdr","hdr.com"]);//用的是数组
<button>houdunren</button>
<button>hscms</button>
function show(){ alert(this.innerHTML); } let btn=document.querySelectorAll("button"); for(let i=0;i<btn.length;i++){ btn[i].addEventListener("click",event=>{ // show.apply(event.target);//event.target指向当前的按钮对象 show.call(event.target);//event.target指向当前的按钮对象 }); }
let arr=[1,2,3,4,5];
console.log(Math.max(...arr));
console.log(Math.max.apply(Math,arr));
function Request(){ this.get=function(params){ let str=Object.keys(params).map(k=>`${k}=${params[k]}`).join("&"); let url=`https://baidu.com>${this.url}/${str}`; // console.log(url+"<hr>"); document.write(url+"<hr>") } } function Article(){ this.url="article/lists"; Request.call(this);//call,此处没有传入参数 } let artile=new Article(); artile.get({id:1,cat:"js"}); function User(){ this.url="user/lists"; Request.call(this);//call,此处没有传入参数 } let user=new User(); user.get({id:2,role:"admin"}); let user1=new User(); user1.get({id:2,role:"admin"});