在对象数组或对象对象中查找特定键的所有值

Question

我有一个如下的对象数组

let arr = [
  {
    name: "string 1",
    details: [
      {
        id: 1,
        values: [
          { date: "12-Mar", score: "15" },
          { date: "13-Mar", score: "16" },
          { date: "14-Mar", score: "17" },
          { date: "15-Mar", score: "18" },
        ],
      },
    ],
  },
  {
    name: "string 2",
    details: [
      {
        id: 2,
        values: [
          { date: "12-Mar", score: "16" },
          { date: "13-Mar", score: "17" },
          { date: "14-Mar", score: "18" },
          { date: "15-Mar", score: "19" },
        ],
      },
    ],
  },
  {
    name: "string 3",
    details: [
      {
        id: 2,
        values: [
          { date: "12-Mar", score: "21" },
          { date: "13-Mar", score: "22" },
          { date: "14-Mar", score: "23" },
          { date: "15-Mar", score: "24" },
        ],
      },
    ],
  },
];

我也有与下面的对象对象相同的数据

let obj = {
  "string 1": {
    details: [
      {
        id: 1,
        values: [
          { date: "12-Mar", score: "15" },
          { date: "13-Mar", score: "16" },
          { date: "14-Mar", score: "17" },
          { date: "15-Mar", score: "18" },
        ],
      },
    ],
  },
  "string 2": {
    details: [
      {
        id: 2,
        values: [
          { date: "12-Mar", score: "16" },
          { date: "13-Mar", score: "17" },
          { date: "14-Mar", score: "18" },
          { date: "15-Mar", score: "19" },
        ],
      },
    ],
  },
  "string 3": {
    details: [
      {
        id: "2",
        values: [
          { date: "12-Mar", score: "21" },
          { date: "13-Mar", score: "22" },
          { date: "14-Mar", score: "23" },
          { date: "15-Mar", score: "24" },
        ],
      },
    ],
  },
};

我想以数组的形式查找所有日期和所有分数。 对于对象数组，借助此处的答案 (How to find all values of a specific key in an array of nested objects?)，我能够使用以下代码获得结果。

因为我不想重复日期，所以我创建了一个Set

dates = new Set(getValue(arr, "date"))

但是，对于对象的对象，我无法得到结果。我该怎么做。

另外，我可以选择将我的数据作为对象的array 或对象的object 获取。由于我必须执行大量操作/分析（我将在 D3 库中使用它来构建图表），哪种格式更好？任何人都可以指导吗？谢谢。

Answer 1

您可以使用递归方法（如参考答案中所示）来选择给定键的所有属性。还可以添加一个unique 参数，如果设置为 true，我们将从属性中创建一个 Set 以确保我们不会返回任何重复项：

        
let arr = [ { name: "string 1", details: [ { id: 1, values: [ { date: "12-Mar", score: "15" }, { date: "13-Mar", score: "16" }, { date: "14-Mar", score: "17" }, { date: "15-Mar", score: "18" }, ], }, ], }, { name: "string 2", details: [ { id: 2, values: [ { date: "12-Mar", score: "16" }, { date: "13-Mar", score: "17" }, { date: "14-Mar", score: "18" }, { date: "15-Mar", score: "19" }, ], }, ], }, { name: "string 3", details: [ { id: 2, values: [ { date: "12-Mar", score: "21" }, { date: "13-Mar", score: "22" }, { date: "14-Mar", score: "23" }, { date: "15-Mar", score: "24" }, ], }, ], }, ];
let obj = { "string 1": { details: [ { id: 1, values: [ { date: "12-Mar", score: "15" }, { date: "13-Mar", score: "16" }, { date: "14-Mar", score: "17" }, { date: "15-Mar", score: "18" }, ], }, ], }, "string 2": { details: [ { id: 2, values: [ { date: "12-Mar", score: "16" }, { date: "13-Mar", score: "17" }, { date: "14-Mar", score: "18" }, { date: "15-Mar", score: "19" }, ], }, ], }, "string 3": { details: [ { id: "2", values: [ { date: "12-Mar", score: "21" }, { date: "13-Mar", score: "22" }, { date: "14-Mar", score: "23" }, { date: "15-Mar", score: "24" }, ], }, ], }, };

function getProperties(obj, key, unique = true, result = []) {
    for(let k in obj) {
        if (typeof(obj[k]) === 'object') {
            getProperties(obj[k], key, unique, result);
        } else if (k === key) { 
            result.push(obj[k]); 
        }
    }
    return unique ? [...new Set(result)]: result;
}
    
console.log('Dates (arr):', JSON.stringify(getProperties(arr, 'date', true)))
console.log('Scores (arr):', JSON.stringify(getProperties(arr, 'score', true)))

console.log('Dates (obj):', JSON.stringify(getProperties(obj, 'date', true)))
console.log('Scores (obj):', JSON.stringify(getProperties(obj, 'score', true)))

Answer 2

您可以像这样遍历对象中的顶级键：

for (let key in obj){
    let val = obj[key]

    /* From here you can proceed with finding all values 
       like you did with the array 
    */
}