Question

我有对象数组，如何搜索所有对象并根据属性值对其进行分类

 data = [ 
  {key: 1, val: Mon, week: 0},
  {key: 1, val: Wed, week: 0},
  {key: 1, val: Mon, week: 1},
  {key: 1, val: Mon, week: 1}
  {key: 1, val: Mon, week: 2}
]

期望的输出

week0Array = [{key: 1, val: Mon, week: 0},{key: 1, val: Wed, week: 0}]
week1Array = [{key: 1, val: Mon, week: 1}, {key: 1, val: Mon, week: 1} ]
week2Array = [{key: 1, val: Mon, week: 2}]

我试图在lodash中使用find并保持未定义

_.find(collection, [predicate=_.identity], [fromIndex=0])

Answer 1

您可以像这样使用_.groupBy(collection, [iteratee=_.identity])：

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let data = [ 
  {key: 1, val: 'Mon', week: 0},
  {key: 1, val: 'Wed', week: 0},
  {key: 1, val: 'Mon', week: 1},
  {key: 1, val: 'Mon', week: 1},
  {key: 1, val: 'Mon', week: 2}
]

let weekGroups = _.groupBy(data, d => d.week)

console.log(weekGroups[0])
console.log(weekGroups[1])
console.log(weekGroups[2])

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

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请注意，weekGroups是Object而不是Array。

Answer 2

正如POJS替代方案并假设数据按开始排序，reduce可以创建一个数组，其中的对象按周分组为子数组。如果需要排序，可以在调用reduce之前添加：

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var data = [ 
    {key: 1, val: "Mon", week: 0},
    {key: 1, val: "Wed", week: 0},
    {key: 1, val: "Mon", week: 1},
    {key: 1, val: "Mon", week: 1},
    {key: 1, val: "Mon", week: 2}
];

var result = data.reduce((acc, obj, i) => {
    i && acc[acc.length-1].week == obj.week ?
        acc[acc.length-1].push(obj) :
        acc.push([obj]);

    return acc;
}, []);

console.log(result)

＆＃13;

条件? :中的括号不是必需的，但我认为它们有助于提高可读性。

根据属性值对对象排序

2 个答案: