如何合并对象数组中的对象？

Question

我正在寻找合并一个阵列中所有对象的最佳解决方案

const arrayOfObjects = [
 {name: 'Fred', surname: 'Shultz'}, {name: 'Anne', surname: 'Example'}
];

我想实现: {name: ['Fred', 'Anne'], surname: ['Example', 'Shultz']}

什么是最好的选择(es6)？也许我可以用lodash做那样的事情？我应该使用哪些助手？

Answer 1

您可以通过迭代条目并收集值来减少数组,具体取决于键.

const
    array = [{ name: 'Fred', surname: 'Shultz' }, { name: 'Anne', surname: 'Example' }],
    result = array.reduce((r, o) => {
        Object.entries(o).forEach(([k, v]) => (r[k] = r[k] || []).push(v));
        return r;
    }, Object.create(null));

console.log(result);

Answer 2

用lodash很容易:

grouped = _.mapValues(arrayOfObjects[0], 
    (val, key) => _.map(arrayOfObjects, key))

纯es6

let grouped = {};

for (let obj of arrayOfObjects)
    for (let [key, val] of Object.entries(obj))
        grouped[key] = (grouped[key] || []).concat(val)

如果按键因项目而异,您可以使用类似的东西来收集它们:

grouped = _(arrayOfObjects)
    .flatMap(_.entries)
    .groupBy(0)
    .mapValues(x => _.map(x, 1))
    .value()

Answer 3

你可以这样做:

const arrayOfObjects = [
  {name: 'Fred', surname: 'Shultz'}, {name: 'Anne', surname: 'Example'}
];

const result = {};
arrayOfObjects.forEach(item => {
  Object.keys(item).forEach(key => {
    if (!result[key]) {
      result[key] = [];
    }
    result[key].push(item[key]);
  });
});

console.log(result);

Answer 4

你可以mergeWith像这样使用lodash :

const result = _.mergeWith({}, ...arrayOfObjects, (value, objValue) =>
    (value || []).concat(objValue)
);

例:

const arrayOfObjects = [
    {name: 'Fred', surname: 'Shultz'}, {name: 'Anne', surname: 'Example'}
];

const result = _.mergeWith({}, ...arrayOfObjects, (value, objValue) =>
    (value || []).concat(objValue)
);

console.log(result);

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