es6 数组的方法

1.from()json的数组格式
let json = {
    '0':'amy',
    '1':'ye',
    length:2
};
let arr = Array.from(json)
console.log(arr)
转成数组的形式

2.Array.of()
// 2.数字，字符串等格式转成数组 Array.of()
let arr1 = Array.of(1,2,3,4)
console.log(arr1)//[1,2,3,4]

let arr2 = Array.of('amy','ye')
console.log(arr2)//['amy','ye']

let arr3 = Array.of({name:'123'},{age:12})
console.log(arr3)//[{name:'123'},{age:12}]

 3.find()数组实例方法
let arr = [1,2,3,4,5]
console.log(arr.find(function (value, index, array) {
    // return value >2; //只要找到了第一个满足条件的就不会继续往下找
    // console.log(value)
    // console.log(index)
    // console.log(array)
    return index===1
}))

// 4.fill(value,start,end)使用固定值填充数组
/*
value 填充的值
start 开始的位置
end 结束的位置（包含start，不包含end）
 */
let arr = ['amy','ye','qq'];
console.log(arr.fill('宝宝',0,1))//['宝宝','ye','qq']

5.for of 遍历
// 1.获取数组的value
let arr = ['amy','ye','qq'];
for(let value of arr){
    console.log(value)
}
// 获取key
let arr = ['amy','ye','qq'];
for(let key of arr.keys()){
    console.log(value)
}
// entries()获取条目的key和value
let arr = ['amy','ye','qq'];
for(let [index,value] of arr.entries()){
    console.log(index)
    console.log(value)
}

// 6.entries()
let arr = ['amy','ye','qq'];
let list = arr.entries()
console.log(list.next().value)//[0, "amy"]
console.log('```````````````')
console.log(list.next().value)//[1, "ye"]
console.log('```````````````')
console.log(list.next().value)//[2, "qq"]