ES6/ES2015

function f() {
       var i = 1;
   }
   console.log(1)
    function f1() {
        let j = 1;
    }
    console.log(j)

const data = 100;
   console.log(data);
   data = 10

 const list =[1,2,3]
    console.log(list)
    list[0]=4
    console.log(list)

   let num  = 10;
   console.log(num.toString(8))
   console.log(num.toString(2))
   console.log(num.toString(16))

   let name  = "tony";
   let str1 = "hello,${name}!"
   console.log(str1)
   let str2 = `hello,${name}!`
   console.log(str2)

   let str1 = String("HelloWorld")
   let str2 = String("HelloWorld")
   console.log(str1==str2)
   console.log(str1===str2)
   let s1 = Symbol("HelloWorld")
   let s2 = Symbol("HelloWorld")
   console.log(s1==s2)
   console.log(s1===s2)

const java = Symbol()
const php = Symbol()

 const java = Symbol()
   const php = Symbol()
    var obj = {}
    obj[java] = "java"
    obj[php] ="php"
    console.log(obj[java])
    console.log(obj[php])

 let [a,b,c] = [10,20,30]
    console.log(a,b,c)
let [x,y,...other]=[1,2,3,4,5]
    console.log(x,y,other)
 let {name,age} ={name:"tony",age:20}
   console.log(name,age)

    let list = [10, 20, 30, 40, 50]
    for (let v in list) {
        console.log(v, list[v])
    }
    for (let v of list) {
        console.log(v)
    }

    function sayHello(name = "tony") {
        console.log(`hello ${name}`)
    }

    sayHello()
    sayHello("xiaoming")

function required() {
         throw new Error("参数不能为空")
    }
    function sayHello(name = required()) {
        console.log(`hello ${name}`)
    }
    sayHello("xiaoming")

    let list = [10,20,30];
    //es5
    let newList = list.map(function (value,index) {
        return value*value
    })
    //es6
    console.log(newList)
    newList = list.map((value,index)=>{
        return value*value
    })
    console.log(newList)
    newList =list.map(value => {
        return value*value
    })
    console.log(newList)

    function sum(...args) {
      let result  = 0;
      args.forEach(value => {
          result += value
      })
        return result
    }
    console.log(sum(1,2,3,4))

    class Student{
        constructor(name,age){
            this.name = name;
            this.age = age;
        }
        print(){
            console.log(`${this.name}--${this.age}`)
        }
        static info(){
            console.log('静态类方式')
        }
    }
    let s = new Student("xiaoming",20)
    s.print()
    Student.info()

    class Student{
        constructor(name,age){
            this.name = name;
            this.age = age;
        }
        set gender(v){
            this._gender = v
        }
        get gender(){
            return this._gender
        }
    }
    let s = new Student("xiaoming",20)
    s.gender = "M"
    console.log(s.gender)

 let ajax = function (callback) {
        console.log('执行')
        setTimeout(function () {
            callback&&callback.call()
        },1000)
    }
    ajax(function () {
        console.log('timeout')
    })

    new Promise(function (resolve,reject) {
        //resolve 成功调用
        //reject 失败调用
    })

    let a = 10;
    let promise = new Promise(function (resolve,reject) {
      if (a ==10) {
           resolve("success")
      }else {
           reject("fail")
      }
    })
    promise.then(res=>{
        console.log(res)
    },err =>{
        console.log(err)
    })

  promise.catch(err=>{
        console.log(err)
    })

new Promise(resolve => {
        resolve("aaa")
    }).then(res=>{
        console.log(res)
    })

    let p1 = Promise.resolve("a")
    let p2 = Promise.resolve("b")
    let p3 = Promise.resolve("c")
    Promise.all([p1,p2,p3]).then(res =>{
        let [r1,r2,r3] = res
        console.log(r1,r2,r3)
    })

 let p1 = Promise.resolve("a")
    let p2 = Promise.reject("b")
    let p3 = Promise.resolve("c")
    Promise.race([p1,p2,p3]).then(res =>{
        console.log(res)
    })