Question

我有一个与此相似的json

 {      
    "id": "1",
    "month": "January",
    "type": "inc",
    "Value": "780.00",
    "year": "2018",
  },

 {      
    "id": "2",
    "month": "January",
    "type": "inc",
    "Value": "80.00",
    "year": "2018",
  },
 {      
    "id": "3",
    "month": "February",
    "type": "inc",
    "Value": "100.00",
    "year": "2018",
  },...

现在我需要从对象中获得所有月份的所有Value，因为您可以看到我可能有更多具有相同月份名称的对象。我越来越近地创建了两个带有月列表的数组1和带有值的数组1，但是我被困住了，有人可以引导我找到正确的路径吗？

理想的输出将是得到一个像["January"=>1500, "February"=>2000...]这样的数组，或者有2个数组，其中1个是有收入的月份列表（我已经有了），第二个是这些月份的总收入，就像这样：["January", "February", "March"..]和第二个[1500, 2000, 300...]

Answer 1

您可以使用函数Array.prototype.reduce来按月对每个Value求和。

let arr =  [{          "id": "1",    "month": "January",    "type": "inc",    "Value": "780.00",    "year": "2018",  }, {          "id": "2",    "month": "January",    "type": "inc",    "Value": "80.00",    "year": "2018",  }, {          "id": "3",    "month": "February",    "type": "inc",    "Value": "100.00",    "year": "2018",  }],
    result = arr.reduce((a, {month, Value}) => {
      a[month] = (a[month] || 0) + +Value;
      return a;
    }, Object.create(null));
  
console.log(result);

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Answer 2

您可以

    var fabuaryDate = yourdata
.filter(function(data) { return data.month == "February" })
.map(function(x){return {value: x.Value} })

Answer 3

实际上我几乎无法理解您想要实现的目标。请提供一些示例。如果我对您的理解正确，则可以使用js数组的map函数将每个对象映射到其Value。

let arr = [...];
console.log(arr.map(item => item.Value));

Answer 4

要获得以下格式的结果：

{
  jan : [1,2,3],
  feb : [3,4,5,6],
  april : [3,4,5]
}

执行此操作：

var output = {}
arr.forEach(element => {
   if(!output[element.month]){
      output[month] = new Array();
   }
   output[month].push(element.value);
});

Answer 5

您可以迭代对象，并用要提取的字段的值填充数组，如下所示：

const data = [ {      
    "id": "1",
    "month": "January",
    "type": "inc",
    "Value": 780.00,
    "year": "2018",
  },
  {      
    "id": "2",
    "month": "January",
    "type": "inc",
    "Value": 80.00,
    "year": "2018",
  },
  {      
    "id": "3",
    "month": "February",
    "type": "inc",
    "Value": 100.00,
    "year": "2018",
  }];
  
let dataArray = data.reduce((accum, d) => {
  if(!accum[d.month]) accum[d.month] = 0;
  accum[d.month] += d.Value;
  return accum;
},{});
console.log(dataArray);

Answer 6

尽管您似乎对此处尝试的内容还不够清楚，但这是一个示例，可以用来读取json中的所有值。

function myFunction(item) {
   console.log(item.month + " with the value " + item.Value)
}

var jsonArray = [{"id": "1","month": "January", "type": "inc", "Value": "780.00", "year": "2018" }, { "id": "2",      "month": "January",  "type": "inc",   "Value": "80.00", "year": "2018"  }, { "id": "3", "month": "February",      "type": "inc", "Value": "100.00", "year": "2018" }];

jsonArray.forEach(myFunction);

由于要使用对象数组，因此必须访问该数组中的每个对象，然后获取所需的属性。

希望这项帮助，祝您生活愉快。

Javascript根据另一个值在json中获取值

6 个答案: