将对象数组转换为树形图（Tree Map）所需的层级数据结构

我有一组扁平化的对象数组，需要将其转换为树形图所需的层级数据结构，具体如下：

原始数据 #

[
    {
      "hospital": "hospital 1",
      "drg": "81",
      "Percentage": 96.10584123814279
    },
    {
      "hospital": "hospital 2",
      "drg": "80",
      "Percentage": 96.66666666666667,
      "Incidents": 2.0
    },
    {
      "hospital": "hospital 1",
      "drg": "82",
      "Percentage": 97.1736204576043
    },
    {
      "hospital": "hospital 3",
      "drg": "82",
      "Percentage": 96.58119658119658
    },
    {
      "hospital": "hospital 3",
      "drg": "80",
      "Percentage": 95.83333333333334,
      "Incidents": 3.0
    },
    {
      "hospital": "hospital 3",
      "drg": "81",
      "Percentage": 95.84885577434807
    },
    {
      "hospital": "hospital 4",
      "drg": "82",
      "Percentage": 94.91017964071857,
      "Incidents": 1.0
    },
    {
      "hospital": "hospital 2",
      "drg": "82",
      "Percentage": 95.53072625698324
    },
    {
      "hospital": "hospital 4",
      "drg": "81",
      " Percentage": 95.65987599645705
    },
    {
      "hospital": "hospital 4",
      "drg": "80",
      "Percentage": 96.18320610687023,
      "Incidents": 2.0
    },
    {
      "hospital": "hospital 1",
      "drg": "80",
      "Percentage": 93.5064935064935,
      "Incidents": 4.0
    },
    {
      "hospital": "hospital 2",
      "drg": "81",
      "Percentage": 95.24096385542168
    }
]

预期结果 #

[
{
    "hospital": "hospital 1",
     "children" :[
        {"drg": "81","Percentage": 96.10584123814279},
        {"drg": "82","Percentage": 97.1736204576043},
        {"drg": "80","Percentage": 93.5064935064935}
      ]
    },
  {
    "hospital": "hospital 2",
    "children" :[
        {"drg": "81","Percentage": 95.24096385542168},
        {"drg": "82","Percentage": 95.53072625698324},
        {"drg": "80","Percentage": 96.66666666666667}
      ]
  },
    {
    "hospital": "hospital 3",
    "children" :[
        {"drg": "82","Percentage": 96.58119658119658},
        {"drg": "80","Percentage": 95.83333333333334},
        {"drg": "81","Percentage": 95.84885577434807}
      ]
  },
    {
    "hospital": "hospital 4",
    "children" :[
        {"drg": "82","Percentage": 94.91017964071857},
        {"drg": "81"," Percentage": 95.65987599645705},
        {"drg": "80","Percentage": 96.18320610687023}
      ]
  }
]

解决方案 #

可以通过遍历原始数组，利用对象映射表分组数据，快速构建树形结构：

function flattenToTree(data) {
    const hospitalMap = {};
    const treeResult = [];

    data.forEach(item => {
        const hospital = item.hospital;
        // 提取子节点数据，保留除hospital外的所有字段
        const childNode = {
            drg: item.drg,
            ...('Percentage' in item && { Percentage: item.Percentage }),
            ...(' Percentage' in item && { ' Percentage': item[' Percentage'] }),
            ...('Incidents' in item && { Incidents: item.Incidents })
        };

        // 若当前医院未在映射表中，创建新节点并加入结果数组
        if (!hospitalMap[hospital]) {
            hospitalMap[hospital] = {
                hospital: hospital,
                children: []
            };
            treeResult.push(hospitalMap[hospital]);
        }

        // 将子节点添加到对应医院的children数组
        hospitalMap[hospital].children.push(childNode);
    });

    return treeResult;
}

// 调用示例
const rawData = [/* 插入上述原始数据数组 */];
const treeData = flattenToTree(rawData);
console.log(JSON.stringify(treeData, null, 2));

核心逻辑说明 #

• 映射表去重：用hospitalMap存储每个医院对应的树形节点，避免重复创建相同医院的父节点。
• 子节点提取：遍历每条数据时，提取除hospital外的所有字段作为子节点内容，兼容原始数据中带空格的 Percentage字段。
• 动态构建树形：检查映射表，不存在则创建父节点并加入结果数组，再将子节点追加到对应父节点的children数组中。

内容的提问来源于stack exchange，提问作者Bhabagrahi Behera