Question

我有一个对象数组，我想按日期排序，然后按颜色排序，并使用lodash对事件进行求和

InitialArray = [{"date":"2017-07-26","partner":"partner1","total":102,"occurrence":10},{"date":"2017-07-27","partner":"partner1","total":100,"occurrence":20},{"date":"2017-07-27","partner":"partner1","total":110,"occurrence":25},{"date":"2017-07-27","partner":"partner2","total":105,"occurrence":30}]

我需要按日期排序，然后按合作伙伴排序，并汇总给定日期的总计和发生次数。所以我的最终数组需要看起来像：

FinalArray = [{"date":"2017-07-26","partner":"partner1","total":102,"occurrence":10},{"date":"2017-07-27","partner":"partner1","total":210,"occurrence":45},{"date":"2017-07-27","partner":"partner2","total":105,"occurrence":30}]

我能够以非功能方式获得结果，但我想优化代码并使用lodash以功能方式执行，因为项目已经在使用它。我能够找到一个我可以组合的示例在给定列上，然后使用sum运算符聚合其他字段。但无法找到任何组合2个字段然后聚合的例子。任何帮助表示赞赏。

Answer 1

您可以先对项目进行分组，然后映射聚合值。

＆＃13;

Order
    Transaction
    OrderProduct
        TransactionDetail
            order_product_id // <- needing this is assumed
            transaction_id // <- but also needs this

＆＃13;

var initialArray = [{ date: "2017-07-26", partner: "partner1", total: 102, occurrence: 10 }, { date: "2017-07-27", partner: "partner1", total: 100, occurrence: 20 }, { date: "2017-07-27", partner: "partner1", total: 110, occurrence: 25 }, { date: "2017-07-27", partner: "partner2", total: 105, occurrence: 30 }],
    groups = ['date', 'partner'],
    result = _(initialArray)
        .groupBy(o => groups.map(k => o[k]).join('|'))
        .map((a, k) => ({
            date: a[0].date,
            partner: a[0].partner,
            total: _.sumBy(a, 'total'),
            occurrence: _.sumBy(a, 'occurrence')
        }))
        .value();

console.log(result);

＆＃13;

.as-console-wrapper { max-height: 100% !important; top: 0; }

＆＃13;

Answer 2

我认为这会产生你想要的结果。

＆＃13;

    var a = [   {"date":"2017-07-26","partner":"partner1","total":102,"occurrence":10},
                {"date":"2017-07-27","partner":"partner1","total":100,"occurrence":20},
                {"date":"2017-07-27","partner":"partner1","total":110,"occurrence":25},
                {"date":"2017-07-27","partner":"partner2","total":105,"occurrence":30}
            ];

var out = a.reduce( (s,e,i) => {
    if (i === 0)
        s.push(e);
    else
        if (typeof s.find( ss => ss.date == e.date && ss.partner == e.partner && (ss.total += e.total)) == 'undefined')
            s.push(e);
    return s;
}, []);
    console.log( out );

＆＃13;

按日期对记录排序，然后使用lodash对计数进行着色和聚合

2 个答案: