使用reduce转换js对象

如何解决使用reduce转换js对象

我想写一个函数来传递这个对象

[
  {
    "id": "656DDXFT565xX","name": "Black item","categorues": [
      "Black","White"
    ],"price": 5
  }
]

成为那样的东西

[
    {
        "Black": [
            {
                "id": "656DDXFT565xX","categories": [
                    "Black","White"
                ],"price": 5
            }
        ]
    },{
        "White": [
            {
                "id": "656DDXFT565xX","price": 5
            }
        ]
    }
]

我尝试过 Array.reduce，但我不知道如何呈现它。

如果有人对此有任何后见之明

解决方法

let before = [
  {
    "id": "656DDXFT565xX-BW","name": "Black and white item","categories": [
      "Black","White"
    ],"price": 5
  },{
    "id": "656DDXFT565xX-K","name": "Black item","categories": [
      "Black"
    ],"price": 10
  },{
    "id": "656DDXFT565xX-W","name": "White item","categories": [
      "White"
    ],"price": 15
  }
]

let after = before.reduce(
  (acc,val) => {
    val.categories.forEach(cat => {
      acc[cat] ||= [] 
      // if this fails,use newer version of node,or use
      // if(!acc.cat) acc.cat = []
      
      acc[cat].push(val)
    })
    return acc
  },{}
)

console.log(after)

,

您可以使用 categorues 迭代每个项目的 .map 以获得预期结果。这是使用 lodash 的解决方案：

const data = [
  { "id":"656DDXFT565xX","name":"Colored item","categorues":["Black","White"],"price":5 },{ "id":"656DDXFT565x2","name":"White item","categorues":["White"],{ "id":"656DDXFT565x3","name":"Black item","categorues":["Black"],"price":5 }
];

const _reduceElem = (elem={}) => {
  const { categorues=[] } = elem;
  return _.map( categorues,cat => ({ [cat]: [_.cloneDeep(elem)] }) );
}
const res = _.reduce(data,(acc,item) => {
  acc = [...acc,..._reduceElem(item)];
  return acc;
},[]);

console.log(res);

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.21/lodash.min.js" integrity="sha512-WFN04846sdKMIP5LKNphMaWzU7YpMyCU245etK3g/2ARYbPK9Ub18eG+ljU96qKRCWh+quCY7yefSmlkQw1ANQ==" crossorigin="anonymous"></script>

,

因为您只想提取 categorues 作为键。您不需要使用 reduce，只需使用 map 循环 categorues 就可以了。

const origin = [
  {
    "id": "656DDXFT565xX","categorues": [
      "Black","price": 5
  }
]

const categorues = origin[0].categorues;
const result = categorues.map(item => {
  return {
    [item]: origin
  }
})

console.log(result)