具有单个id的多个数组在java脚本中基于id执行此单个数组？

Question

我有一个像这样的多个数组的列表

jquery([
 {
  id:2,
  count:23,
  numberOfType:34
},
{
  id:2,
  count2:53,
  numberOfType2:34
},
{
  id:2,
  count3:53,
  numberOfType3:34
},
{
  id:2,
  count:23,
  numberOfType:34
},
{
  id:21,
  count2:53,
  numberOfType2:34
},
{
  id:21,
  count3:53,
  numberOfType3:34
},
])

我希望这个数据合成

喜欢

jquery([
  {
  id:2,
  count:23,
  count2:53,
  count3:53,
  numberOfType:34,
  numberOfType2:34,
 numberOfType3:34
},
{
  id:21,
  count:23,
  count2:53,
  count3:53,
  numberOfType:34,
  numberOfType2:34,
 numberOfType3:34
}
])

Answer 1

通过Array#reduce迭代数组并检查是否存在。如果已存在具有当前项ID的项，则通过Object#assign将属性复制到其中。

const data = [
   {
      id:2,
      count:23,
      numberOfType:34
   },
   {
      id:2,
      count2:53,
      numberOfType2:34
   },
   {
      id:2,
      count3:53,
      numberOfType3:34
   },
   {
      id:2,
      count:23,
      numberOfType:34
   },
   {
      id:21,
      count2:53,
      numberOfType2:34
   },
   {
      id:21,
      count3:53,
      numberOfType3:34
   }
];

const reduced = data.reduce((acc, item) => {
  
  const found = acc.find(i => i.id === item.id);
  
  if(found) {
     Object.assign(found, item);
  } else {
     acc.push(Object.assign({}, item));
  }
  
  return acc;
}, []);

console.log(reduced);

Answer 2

只需使用Object.assign和Object.values

即可

var output = Object.values( arr.reduce( (a, c) => 
         (a[c.id] = Object.assign( {}, a[c.id], c ), a) ,  //assign new properties to a[c.id]
         {} ) ); //accumulator 

<强>演示

var arr = [{
    id: 2,
    count: 23,
    numberOfType: 34
  },
  {
    id: 2,
    count2: 53,
    numberOfType2: 34
  },
  {
    id: 2,
    count3: 53,
    numberOfType3: 34
  },
  {
    id: 2,
    count: 23,
    numberOfType: 34
  },
  {
    id: 21,
    count2: 53,
    numberOfType2: 34
  },
  {
    id: 21,
    count3: 53,
    numberOfType3: 34
  },
];
var output = Object.values(arr.reduce((a, c) =>
  (a[c.id] = Object.assign({}, a[c.id], c), a), //assign new properties to a[c.id]
  {})); //accumulator

console.log( output );

Answer 3

您可以Map和id分组。

var array = [{ id: 2, count: 23, numberOfType: 34 }, { id: 2, count2: 53, numberOfType2: 34 }, { id: 2, count3: 53, numberOfType3: 34 }, { id: 2, count: 23, numberOfType: 34 }, { id: 21, count2: 53, numberOfType2: 34 }, { id: 21, count3: 53, numberOfType3: 34 }],
    result = [
        ...array
            .reduce((m, o) => m.set(o.id, Object.assign(m.get(o.id) || {}, o)), new Map)
            .values()
    ];

console.log(result);

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

Answer 4

您可以使用new Class并检查累加器中是否存在ID，否则附加

＆＃13;

＆＃13;

reduce

＆＃13;

＆＃13;

＆＃13;