一. 对象扩展方法 Object.fromEntries

// 二维数组 转为对象
const result = Object.fromEntries([
      ['name','王蓉'],['study','skill']
])
console.log(result);      //{name:'wangrong',study:'skill'}

//Map
const m = new Map();
m.set('name','wangrong')
console.log(m);      //{'name' => 'wangrong'}

const result1 = Object.fromEntries(m);
console.log(result1);      //{name:'wangrong'}

// Object.entries Es8
const arr = Object.entries({
      name: 'wangronbg'
})
console.log(arr);      //[Array(2)] [['name','wangrong']]