使用纯 javascript 将对象数组转换为具有属性类型数组的映射数组

Question

我需要显示一个公司列表，其中包含与每个公司相关的所有用户（关注者）：这是当前的数组数据结构：

[
  {
    company:"CompanyName1",
    type:"Type1",
    info: {}
    userId: "U001"
  },
  {
    company:"CompanyName1",
    type:"Type1",
    info: {}
    userId: "U002"
  },
  {
    company:"CompanyName1",
    type:"Type1",
    info: {}
    userId: "U003"
  },
  {
    company:"CompanyName2",
    type:"Type2",
    info: {}
    userId: "U001"
  }
]

我需要这种格式的数据结构，使用纯 javascript（映射、缩减等）

[
  {
    company:"CompanyName1",
    type:"Type1",
    info:{},
    userIds: ["U001", "U002", "U003"]
  },
  {
   company:"CompanyName2",
   type:"Type2",
   info:{},
   userIds: ["U001"]
  }
]

Answer 1

这应该有效，您的结果存储在 companyList 数组中 - 如果您需要了解这里发生的事情，请告诉我。基本上它只是一个简单的 forEach.

 let origionalData = [{
        "company": "CompanyName1",
        "type": "Type1",
        "info": "",
        "userId": "U001"
    },
    {
        "company": "CompanyName1",
        "type": "Type1",
        "info": "",
        "userId": "U002"
    },
    {
        "company": "CompanyName1",
        "type": "Type1",
        "info": "",
        "userId": "U003"
    },
    {
        "company": "CompanyName2",
        "type": "Type2",
        "info": "",
        "userId": "U001"
    }
];

然后：

let companyList = []

origionalData.forEach((data, index) => {

    if (companyList[data.company]) {
        companyList[data.company].userIds.push(data.userId)
    } else {
        companyList[data.company] = {
            "type": data.type,
            "info": "",
            "userIds": [data.userIds]
        }
    }
})

console.log(companyList); // Here are the results!

Answer 2

您可以使用散列 table 对相同的公司进行分组。

var array = [{ company: "CompanyName1", type: "Type1", info: {}, userId: "U001" }, { company: "CompanyName1", type: "Type1", info: {}, userId: "U002" }, { company: "CompanyName1", type: "Type1", info: {}, userId: "U003" }, { company: "CompanyName2", type: "Type2", info: {}, userId: "U001" }],
    hash = Object.create(null),
    result = [];

array.forEach(function (o) {
    if (!hash[o.company]) {
        hash[o.company] = { company: o.company, type: o.type, info: o.info, userIds: [] }
        result.push(hash[o.company]);
    }
    hash[o.company].userIds.push(o.userId);
});

console.log(result);

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

Answer 3

因此，我对您需要的数据做了一些假设。我不确定你是想按给定的方式在每个对象中使用公司字段，还是增加它，所以我按给定的方式使用它。我还返回了一个有效对象，因为您要求的结果无效。不管怎样，这是你想要的吗？

const original = [
  {
    "company":"CompanyName1",
    "type":"Type1",
    "info": {},
    "userId": "U001"
  },
  {
    "company":"CompanyName1",
    "type":"Type1",
    "info": {},
    "userId": "U002"
  },
  {
    "company":"CompanyName1",
    "type":"Type1",
    "info": {},
    "userId": "U003"
  },
  {
    "company":"CompanyName2",
    "type":"Type2",
    "info": {},
    "userId": "U001"
  }
];

const result = original.reduce((acc, item) => {
  acc.push({
    [item.company]: {
      type: item.type,
      info: item.info,
      userId: item.userId
    }
  });
  return acc;
}, []);

使用纯 javascript 将对象数组转换为具有属性类型数组的映射数组

Turn an array of objects into a map array with a property of type array using pure javascript

javascript

reduce

mapreduce

使用纯 javascript 将对象数组转换为具有 属性 类型数组的映射数组

Turn an array of objects into a map array with a property of type array using pure javascript

javascript

reduce

mapreduce

使用纯 javascript 将对象数组转换为具有属性类型数组的映射数组