Javascript根据条件减少到对象组

2019年7月20日 190次阅读

我有以下数据：

var foo = [
    {'MonthNo' : 03, 'CustomerTypeID' : 1 , 'TotalSales' : 45 },
    {'MonthNo' : 03, 'CustomerTypeID' : 2 , 'TotalSales' : 64 },
    {'MonthNo' : 03, 'CustomerTypeID' : 4 , 'TotalSales' : 89 },
    {'MonthNo' : 03, 'CustomerTypeID' : 5 , 'TotalSales' : 42 },
    {'MonthNo' : 04, 'CustomerTypeID' : 1 , 'TotalSales' : 66 },
    {'MonthNo' : 04, 'CustomerTypeID' : 2 , 'TotalSales' : 78 },
    {'MonthNo' : 04, 'CustomerTypeID' : 5 , 'TotalSales' : 20 },
    {'MonthNo' : 04, 'CustomerTypeID' : 6 , 'TotalSales' : 10 }
];

我想将此转换为以下内容

{'MonthNo' : 03, 'CustomerTypeID' : 1 , 'TotalSales' : 198 },
{'MonthNo' : 03, 'CustomerTypeID' : 5 , 'TotalSales' : 42 },
{'MonthNo' : 04, 'CustomerTypeID' : 1 , 'TotalSales' : 144 },
{'MonthNo' : 04, 'CustomerTypeID' : 5 , 'TotalSales' : 20 },
{'MonthNo' : 04, 'CustomerTypeID' : 6 , 'TotalSales' : 10 }

对于每个MonthNo,除了CustomerTypeID 5& 6,我想加上TotalSales值.
对于Ex：MonthNo 03,对于CustomerTypeID 1,2,4,它们的TotalSales值总计为198.对于MonthNo 04,CustomerTypeID 1的TotalSales值和& 2加起来为144.

我尝试使用reduce功能

var result = foo.reduce(function(obj,item){
    // code here
},{});

但是,我无法将它们隔离以获得所需的结果.任何帮助将不胜感激.

最佳答案 您可以检查特殊情况并使用哈希表来引用正确的对象进行计数.

var foo = [{ MonthNo: '03', CustomerTypeID: 1, TotalSales: 45 }, { MonthNo: '03', CustomerTypeID: 2, TotalSales: 64 }, { MonthNo: '03', CustomerTypeID: 4, TotalSales: 89 }, { MonthNo: '03', CustomerTypeID: 5, TotalSales: 42 }, { MonthNo: '04', CustomerTypeID: 1, TotalSales: 66 }, { MonthNo: '04', CustomerTypeID: 2, TotalSales: 78 }, { MonthNo: '04', CustomerTypeID: 5, TotalSales: 20 }, { MonthNo: '04', CustomerTypeID: 6, TotalSales: 10 }],
    result = foo.reduce(function (hash) {
        return function (r, a) {
            var cType = [5, 6].indexOf(a.CustomerTypeID) === -1 ? 1 : a.CustomerTypeID,
                key = [a.MonthNo, cType].join('|');

            if (!hash[key]) {
                hash[key] = { MonthNo: a.MonthNo, CustomerTypeID: cType, TotalSales: 0 };
                r.push(hash[key]);
            }
            hash[key].TotalSales += a.TotalSales;
            return r;
        }
    }(Object.create(null)), []);
 
console.log(result);
.as-console-wrapper { max-height: 100% !important; top: 0; }
点赞