javascript - 从多个对象中获取唯一键

Question

如果我有一个像这样的对象数组:

var mountains = [
    { name: 'Kebnekaise', elevation: 2106 },
    { name: 'Mount Ngauruhoe', elevation: 2291, comment: 'aka Mount Doom' }
];

如何获取所有唯一键，即 ['name', 'elevation', 'comment']？

Answer 1

在 ECMAScript 2015 中，它非常简单:

let mountains = [
  { name: 'Kebnekaise', elevation: 2106 },
  { name: 'Mount Ngauruhoe', elevation: 2291, comment: 'aka Mount Doom' }
];

let uniqueKeys = Object.keys(Object.assign({}, ...mountains));