Question

如果其他对象中的键是相同的，则如何检入多个对象，然后对这些值求和。

例如，在这种情况下，我想要将A和B的所有值相加。

[{
    "firstObject": 1,
    "subObjects": [{
        "A": 1,
        "B": 2
    }, {
        "C": 3,
        "D": 1
    }]
}, {
    "firstObject": 2,
    "subObjects": [{
        "A": 0,
        "C": 5
    }, {
        "B": 2,
        "D": 2
    }]
}]

有什么想法吗？

Answer 1

您可以使用reduce()方法，然后返回对象作为结果。您还可以在结果let {A, B} = result上使用对象解构来获取单独变量中的值。

＆＃13;

const data = [{"firstObject":1,"subObjects":[{"A":1,"B":2},{"C":3,"D":1}]},{"firstObject":2,"subObjects":[{"A":0,"C":5},{"B":2,"D":2}]}];
const result = data.reduce((r, {subObjects}) => {
  subObjects.forEach(({A, B}) => {
    if(A) r.A = (r.A || 0) + A
    if(B) r.B = (r.B || 0) + B
  })
  return r;
}, {})

console.log(result)

＆＃13;

Answer 2

您可以对array#reduce对象中的每个键使用subObject，对该值求和并将其添加到对象中。

＆＃13;

const data = [{ "firstObject": 1, "subObjects": [{ "A": 1, "B": 2 }, { "C": 3, "D": 1 } ] }, { "firstObject": 2, "subObjects": [{ "A": 0, "C": 5 }, { "B": 2, "D": 2 } ] } ],
    result = data.reduce((r,{subObjects}) => {
      subObjects.forEach(o => {
        Object.keys(o).forEach(k => {
          r[k] = (r[k] || 0) + o[k];
        });
      });
      return r;
    },{});
console.log(result);

＆＃13;

Answer 3

使用函数reduce对值进行求和的替代方案以及用于选择特定值的targets数组，在这种情况下，只有[A, B]

＆＃13;

var array = [{    "firstObject": 1,    "subObjects": [{        "A": 1,        "B": 2      },      {        "C": 3,        "D": 1      }    ]  },  {    "firstObject": 2,    "subObjects": [{        "A": 0,        "C": 5      },      {        "B": 2,        "D": 2      }    ]  }],
    targets = ['A', 'B'],
    result = array.reduce((a, c) => {
       targets.forEach(t => a[t] = c.subObjects.reduce((aa, ac) => aa + (ac[t] || 0), a[t] || 0));
       return a;
    }, {});

console.log(result);

＆＃13;

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

＆＃13;

<script src="https://codepen.io/egomezr/pen/dmLLwP.js"></script>

＆＃13;

Answer 4

您可以使用reduce()和spread syntax来获取所需的结果。

<强>样本

＆＃13;

const data = [{
    "firstObject": 1,
    "subObjects": [{
        "A": 1,
        "B": 2
    }, {
        "C": 3,
        "D": 1
    }]
}, {
    "firstObject": 2,
    "subObjects": [{
        "A": 0,
        "C": 5
    }, {
        "B": 2,
        "D": 2
    }]
}];

let result = data.reduce((r,{subObjects})=>[...r,...subObjects],[]).reduce((r,{A,B})=>{
	r['A']+=+(A||0);
	r['B']+= +(B||0);
	return r;
},{A:0,B:0});

console.log(result)

＆＃13;

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

＆＃13;

检查重复键并将多个对象中的值相加

4 个答案: