a.解构参数: function breakfast（dessert,drink,{location,restaurant}={}）{ console.log(dessert,drink,location,restaurant); } breakfast('甜甜圈','牛奶',{location:'长沙',restaurant:'巴黎甜点'}); b.函数名称：name function breakfast(){};//函数声明的方式创建函数 console.log(breakfast.name) //breakfast let breakfast = function(); //匿名函数赋值 console.log(breakfast.name) //breakfast let breakfast = function superBreakfast(); //函数声明之后赋值优先级更高 console.log(breakfast.name) //superBreakfast; c.箭头函数： let breakfast = dessert => dessert; function breakfast(dessert){return dessert }; let breakfast = (dessert,drink)=>{return dessert + drink}; function breakfast(dessert,drink){return dessert + drink}; d.对象赋值： let breakfast = {dessert:"cake",drink:"milk"}; let breakfast2 = {};//只能为对象其他无法赋值 Object.assign(breakfast,breakfast2); console.log(breakfast2)//{dessert:"cake",drink:"milk"} e.数组： let arr = [1, 2, 3, 'cc', 5, 1, 9]; console.log(arr.find((value, keys, arr) => { return value > 2; }))//3 const list = [{'name':'1',index:1},{'name':'2'},{'name':'1'}] let list2 = list.find(i=>i.name==='1') let list3 = list.filter(i=>i.name==='1') console.log(list); [ { name: '1', index: 1 }, { name: '2' }, { name: '1' } ] console.log(list2); { name: '1', index: 1 } console.log(list3);[ { name: '1', index: 1 }, { name: '1' } ] find 返回的是一个对象，filter 返回的是一个数组，都不会改变原数组 f.classes： class breakfast { constructor(food){ //可将初始化的数据放进去 this.food = food; } cook(){ console.log(this.food); } } let wanhao = new breakfast("cake"); wanhao.cook()//cake g.继承-extends: class Person{ constructor(name,birthday){ this.name = name ; this.birthday = birthday; } intro(){ return ${name},${birthday}; } } class Chef extends Person{ constructor(name , birthday){ super(name,birthday); } } let wanhao = new Chef('wanghao','1886-05-12'); console.log(wanhao.intro());//'wanghao','1886-05-12' h.Set:(对象或数组里面的数据不能是重复的) let arr = [1, 2, 3, 'cc', 5, 1, 9,2,3]; let arr2 = []; let desserts = new Set(arr); desserts.forEach(item => { arr2.push(item); }) console.log(arr2); I.数组的拷贝： 1.let arr = [1,2,3]; let arr2 = JSON.parse(JSON.stringify(arr)); 2.let arr2 = [...arr];