javascript - 使用 Lodash 拔取嵌套对象的键

Question

我有这样的结构:

      areas = {
        'sample-id': {
          title: 'Area 1',
          type: 'outdoor',
          boundaries: [
            'fm-86071.92984676428', 'fm-33663.81255808968',
            'fm-22124.724922206497', 'fm-98002.82095021005'
          ]
        },
        'sample-id-2': {
          title: 'Area 2',
          type: 'meetingroom',
          boundaries: [
            'fm-39517.47084731459', 'fm-79087.74683350614',
            'fm-39153.28644344014', 'fm-38873.63204123109',
            'fm-67952.07827771583', 'fm-53210.58304837807',
          ]
        }
      };

我需要获取一个由每个区域的所有 title 键组成的数组，即所需的输出 = ['Area 1', 'Area 2']。< br/>我发现 _.pluck 已被删除，取而代之的是 _.map，但使用

_.map(areas, 'title')

..需要区域为数组。
我还认为使用 _.values 将对象转换为数组，然后使用 _.map 应该可以，但是有没有直接或首选的方法？
编辑:我还想保留键的顺序
编辑2:好吧，我忘记了对象中的键没有顺序，所以保留它，我想我会使用Array.prototype.sort()

Answer 1

Lodash 的 _.map() 也适用于对象:

var areas = {"sample-id":{"title":"Area 1","type":"outdoor","boundaries":["fm-86071.92984676428","fm-33663.81255808968","fm-22124.724922206497","fm-98002.82095021005"]},"sample-id-2":{"title":"Area 2","type":"meetingroom","boundaries":["fm-39517.47084731459","fm-79087.74683350614","fm-39153.28644344014","fm-38873.63204123109","fm-67952.07827771583","fm-53210.58304837807"]}};

var result = _.map(areas, 'title');

console.log(result);

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