Question

我有这个数组，数组中的每个对象只有一个键：

[{ "hello": "value1" }, { "there": "value2" }, { "everybody": "value3" }]

我想将所有键提取到一个数组中，以便我想要的结果是：

["hello", "there", "everybody"]

在Lodash或vanilla JavaScript（最好是ES6）中，这是一种简洁的方法吗？

Answer 1

您可以将Object.keys与let arr = [{ "hello": "value1" }, { "there": "value2" }, { "everybody": "value3" }]; let keys = [].concat(...arr.map(Object.keys)); console.log(keys);一起使用。

＆＃13;

editing

＆＃13;

Answer 2

使用Object#assign合并到单个对象，并使用Object#keys从对象中检索键：

const arr = [{ "hello": "value1" }, { "there": "value2" }, { "everybody": "value3" }];

const keys = Object.keys(Object.assign({}, ...arr));

console.log(keys);

ES5版本使用lodash的_.assign()与_.spread()合并为一个对象，_.keys()来获取密钥：

var arr = [{ "hello": "value1" }, { "there": "value2" }, { "everybody": "value3" }];

var keys = _.keys(_.spread(_.assign)(arr))

console.log(keys);

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.4/lodash.min.js"></script>

Answer 3

您可以将数组map与对象keys结合使用：

const array = [{ "hello": "value1" }, { "there": "value2" }, { "everybody": "value3" }];

const result = array.map((el) => Object.keys(el)[0]);

Answer 4

＆＃13;

var x = [{ "hello": "value1" }, { "there": "value2" }, { "everybody": "value3" }];

console.log(x.map(function(obj){return Object.keys(obj)[0]}));

＆＃13;

Answer 5

以下是使用lodash的flatMap：

的解决方案

let result = _.flatMap(data, _.keys);

Answer 6

保留重复键的本机ES5解决方案将是：

var objects = [{ "hello": "value1" }, { "there": "value2" }, { "everybody": "value3" }];
var keys = [];
for (var obj in objets) {
    keys.push(Object.keys(obj)[0]);
}

JavaScript从对象数组中获取键数组

6 个答案: