Javascript 按值求可变长度的对象数组的和

对不同长度的对象数组求和的最佳方法如下：

data = [{"category":"category1","months":{"1":34,"2":67,"3":29,...}
{"category":"category2","months":{"1":34,"2":627,"3":292,...}
{"category":"category3","months":{"1":46,"2":665,"3":129,...}
{"category":"category4","months":{"1":624,"2":667,"3":629,...}
{"category":"category5","months":{"1":32,"2":637,"3":299,...}
}]

我想基本上按月分组，求和并分配给一个总类别。因此，我会得到一个新对象，它看起来像下面这样，我会推送到我的数据对象：

{"category":"total","months":{"1":770,"2":2663,"3":1378,...}

我最终会：

data = [{"category":"category1","months":{"1":34,"2":67,"3":29,...}
{"category":"category2","months":{"1":34,"2":627,"3":292,...}
{"category":"category3","months":{"1":46,"2":665,"3":129,...}
{"category":"category4","months":{"1":624,"2":667,"3":629,...}
{"category":"category5","months":{"1":32,"2":637,"3":299,...}
{"category":"total","months":{"1":770,"2":2663,"3":1378,...}
}]

---

使用

Array.prototype.reduce

和

hash table

获取“total”对象，然后将其推回到数据中以获取所需的数据结构

请参见下面的演示：

var数据=[{“类别”：“类别1”，“月份”：{“1”：34，“2”：67，“3”：29}，{“类别2”，“月份”：{“1”：34，“2”：627，“3”：292}}，{“类别3”，“月份”：{“1”：46，“2”：665，“3”：129}，{“类别”：“类别4”，“月份”：{“1”：624，“2”：667，“3”：629}，{“类别5”，“月份”：“类别5”，“32”：637}
var result=data.reduce（函数（散列）{
返回函数（p，c）{
Object.key（c.months）.forEach（函数（e）{
如果（以p月为单位）{
p、 月[e]+=c.月[e]；
}否则{
p、 月[e]=+c.月[e]；
}
});
返回p；
}
}（Object.create（null）），{类别：“总计”，月份：{}）；
控制台日志（结果）；
//现在把这个推到数据上
数据推送（结果）；
//控制台日志（数据）
.as控制台包装{top:0；最大高度：100%！重要；}
let data = [
{"category":"category1","months":{"1":34,"2":67,"3":29}},
{"category":"category2","months":{"1":34,"2":627,"3":292}},
{"category":"category3","months":{"1":46,"2":665,"3":129}},
{"category":"category4","months":{"1":624,"2":667,"3":629}},
{"category":"category5","months":{"1":32,"2":637,"3":299}},
];

let total = {"category":"total","months":{}};

data.forEach(category => {
      for(let prop in category.months){
          if (total.months[prop]){
            total.months[prop] += category.months[prop];
          }
          else{
            total.months[prop] = category.months[prop];
          }
      }
});

data.push(total);