数组和对象的相互转化

1.对象转数组

let arrObj = [
    { name: '郭德纲', englishName: "guodegang" },
    { name: '于谦', englishName: "yuqian" },
    { name: '孟鹤堂', englishName: "menghetang" },
    { name: '周久良', englishName: "zhoujiuliang" },
]

let arr = Array.from(arrObj, ({ name }) => name)  //  ["郭德纲", "于谦", "孟鹤堂", "周久良"]

// {name} 属于解构赋值 将遍历的每一项中的 name 属性赋值给 name
// => 后面省略了 return 箭头函数的简写

2.数组转对象

let arr = [1, 2, 3, 4, 5, 6, 7]

let obj = { ...arr } // ... 展开运算符

console.log(obj) // {0: 0, 1: 1, 2: 2, 3: 3, 4: 4, 5: 5}