javascript - 遍历返回空值的大对象

问题描述

我从互联网上复制了一个代码，它在其中搜索一个 json 集合 - 找到相关的键并根据操作返回它们的值，无论是整体还是单个数组。问题是它只搜索它找到的值并总结它们。我想要一个附加功能来查找哪个键具有空值。请如果有人可以调查一下。

function perform(keys, operation) {
  function visit(object) {
    Object.entries(object).forEach(([k, v]) => {
      if (k in indices) return fn(result, indices[k], v);
      if (v && typeof v === "object") visit(v);
    });
  }

  var result = [],
    indices = Object.assign({}, ...keys.map((k, i) => ({ [k]: i }))),
    fn = {
      notsum: function(target, key, value) {
        if (target[key] === undefined) {
          target[key] = value;
          return;
        }
        if (!Array.isArray(target[key])) {
          target[key] = [target[key]];
        }
        target[key].push(value);
      },
      sum: function(target, key, value) {
        target[key] = (target[key] || 0) + value;
      }
    }[operation === "total" ? "sum" : operation];

  visit(data);

  //to add functionality here to get the keys with values, even if they are null

  //end
  return operation === "total" ? result.reduce((a, b) => a + b) : result;
}

这个怎么运作

console.log(perform(["WA1", "WA3", "RAE1"], "notsum")); // [3, 2, 1]
console.log(perform(["WA1", "WA3", "RAE1"], "total"));  // 6

JSON 对象可以简单也可以复杂

var data = {
  version: "1.0",
  submission: "editing",
  WebData: {
    WA1: 3,
    WA3: 2,
    WAX: "NEO",
    WebGroup: [{ Web1: 3, Web2: 0 }, { Web1: 4, Web2: 1 }]
  },
  NonWebData: { NWA1: 3, NWA2: "INP", NWA3: 2 },
  FormInputs: { FM11: 3, FM12: 1, FM13: 2 },
  RawData: {
    RawOverview: { RAE1: 1, RAE2: 1 },
    RawGroups: [
      {
        name: "A1",
        id: "1",
        data: {
          AD1: "period",
          AD2: 2,
          AD3: 2,
          transfers: [
            { type: "in", TT1: 1, TT2: 2 },
            { type: "out", TT1: 1, TT2: 2 }
          ]
        }
      },
      {
        name: "A2",
        id: "2",
        data: {
          AD1: "period",
          AD2: 2,
          AD3: 2,
          transfers: [
            { type: "in", TT1: 1, TT2: 2 },
            { type: "out", TT1: 1, TT2: 2 }
          ]
        }
      }
    ]
  },
  Other: { O1: 1, O2: 2, O3: "hello" },
  AddedBy: "name",
  AddedDate: "11/02/2019"
};

该功能确实返回索引，我拥有所有键，但我想要键值对，所以我知道数组中的哪一个根本不存在。写在函数中的代码给我

["WA1", "WA3", "RAE1"]
[2, null, null]

现在，它只查找该值是否存在，并将它们相加并给我 2 作为结果。

提前谢谢了

标签： javascriptjsondictionarysearch

您可以编写一个函数，递归访问对象树中的所有节点并执行您想要的操作。下面是一个示例函数，它sum和“getBykey”。

function perform(obj, keys = [], operation = "getByKey") {
  const results = [];
  let sum = 0;

  // Define a fucntion that traverses all nodes in your object tree
  const visit = (obj, keys = [], operation = "getByKey") => {
    if (obj && typeof obj === "object") {
      Object.entries(obj).forEach(([key, value]) => {
        if (keys.includes(key)) {
          // You can add more if_block/switch_case for more operations
          if (operation === "sum" && !isNaN(value)) {
            sum += value;
          } else {
            results.push({ [key]: value });
          }
        }
        visit(value, keys, operation);
      });
    }
  }

  // Traverse the object tree
  visit(obj, keys, operation);

  return operation === "sum" ? sum : results;
}

const getByKey = perform(data, ["WA1", "WA3", "RAE1", "AD1"]);
const sum = perform(data, ["WA1", "WA3", "RAE1"], 'sum');

console.log(sum);
console.log(getByKey);

javascript - 遍历返回空值的大对象

问题描述

解决方案

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