使用 JAVASCRIPT 对 JSON 数据求和和分组 [重复]答案

【问题标题】：SUM AND GROUPING JSON DATA USING JAVASCRIPT [duplicate]使用 JAVASCRIPT 对 JSON 数据求和和分组 [重复]
【发布时间】：2022-02-04 17:45:11
【问题描述】：

很抱歉，如果以前有人问过这个问题，但我找不到一个很好的例子来说明我正在努力完成的事情。也许我只是没有在寻找正确的东西。如果某处对此有解释，请纠正我。

假设我有这样的数据：

data = [
{"no":1,"location":"New York","transaction":3000},
{"no":2,"location":"Tokyo","transaction":3000},
{"no":3,"location":"New York","transaction":3000},
{"no":4,"location":"Amsterdam","transaction":3000},
{"no":5,"location":"Manchester","transaction":3000},
{"no":6,"location":"New York","transaction":3000},
{"no":7,"location":"Tokyo","transaction":3000},
{"no":8,"location":"Tokyo","transaction":3000},
{"no":9,"location":"New York","transaction":3000},
{"no":10,"location":"Amsterdam","transaction":3000}
]

我想要的是这样的输出：

result = [
{"location":"New York","transaction":12000},
{"location":"Tokyo","transaction":9000},
{"location":"Amsterdam","transaction":6000}
{"location":"Manchester","transaction":3000}
]

所以我想做的是根据位置对数据进行分组，并对位置相同的事务求和，然后将数据推送到另一个数组。我不知道从哪里开始，需要一些帮助来解决这个问题或使用 Javascript 解决这个问题的任何建议。谢谢

【问题讨论】：

这个可以解决吗：stackoverflow.com/questions/40774697/…
您可能需要使用循环，如for()，以及push() 对象到一个新的空数组，诸如此类。这是经典的数据操作。请试一试，展示您的尝试，如果您遇到特定问题，我们可以提供帮助
@JeremyThille 这个问题已经被问了几千次了，没有意义再次回答。
这正是我没有回答的原因。不过，我想给出提示并没有什么坏处。
@Jamiec 感谢提供信息的伙伴，就像我说的，也许我没有正确搜索。我再试一次

标签： javascript json

【解决方案1】：

工作演示：

// Input array
const data = [
{"no":1,"location":"New York","transaction":3000},
{"no":2,"location":"Tokyo","transaction":3000},
{"no":3,"location":"New York","transaction":3000},
{"no":4,"location":"Amsterdam","transaction":3000},
{"no":5,"location":"Manchester","transaction":3000},
{"no":6,"location":"New York","transaction":3000},
{"no":7,"location":"Tokyo","transaction":3000},
{"no":8,"location":"Tokyo","transaction":3000},
{"no":9,"location":"New York","transaction":3000},
{"no":10,"location":"Amsterdam","transaction":3000}
];

// result array
const resultArr = [];

// grouping by location and resulting with an object using Array.reduce() method
const groupByLocation = data.reduce((group, item) => {
  const { location } = item;
  group[location] = group[location] ?? [];
  group[location].push(item.transaction);
  return group;
}, {});

// Finally calculating the sum based on the location array we have.
Object.keys(groupByLocation).forEach((item) => {
    groupByLocation[item] = groupByLocation[item].reduce((a, b) => a + b);
    resultArr.push({
        'location': item,
      'transaction': groupByLocation[item]
    })
})

console.log(resultArr)

【讨论】：