如何对比多层嵌套对象数组 按Key匹配筛选Value一致的条目

需求说明 #

给定两个结构相同的嵌套对象数组，先按顶层Key字段匹配对应分组，再对同一分组下的子项数组，筛选出两个数组中Key和Value均完全一致的子项，最终输出仅保留匹配项的结果数组。

输入数据 #

arr1 结构 #

arr1 =[
    {
        "Key": "Exterior",
        "Value": [
            {
                "Key": "Wheel Covers",
                "Value": "Center Cap"
            },
            {
                "Key": "Body Coloured Bumpers",
                "Value": "-"
            },
            {
                "Key": "Body Coloured Outside Door Handles ",
                "Value": "yes"
            },
            {
                "Key": "Body Side Molding",
                "Value": "-"
            },
            {
                "Key": "High-Mounted Stop Lamp",
                "Value": "yes"
            }
        ]
    },
    {
        "Key": "Interiors",
        "Value": [
            {
                "Key": "Seat Upholstery",
                "Value": "Vinyl"
            },
            {
                "Key": "B & C Pillar Upper Trims",
                "Value": "-"
            },
            {
                "Key": "C Pillar Lower Trim (Molded)",
                "Value": "yes"
            },
            {
                "Key": "Dual-tone Interiors",
                "Value": "yes"
            },
            {
                "Key": "Silver Accent Inside Door Handles",
                "Value": "-"
            },
            {
                "Key": "Silver Accent on Center Garnish",
                "Value": "-"
            },
            {
                "Key": "Silver Accent on Louvers",
                "Value": "-"
            },
            {
                "Key": "Silver Accent on Steering Wheel",
                "Value": "-"
            }
        ]
    }
]

arr2 结构 #

arr2 =[
    {
        "Key": "Exterior",
        "Value": [
            {
                "Key": "Wheel Covers",
                "Value": "Full"
            },
            {
                "Key": "Body Coloured Bumpers",
                "Value": "yes"
            },
            {
                "Key": "Body Coloured Outside Door Handles ",
                "Value": "yes"
            },
            {
                "Key": "Body Side Molding",
                "Value": "-"
            }
        ]
    },
    {
        "Key": "Interiors",
        "Value": [
            {
                "Key": "Seat Upholstery",
                "Value": "Fabric+Vinyl"
            },
            {
                "Key": "B & C Pillar Upper Trims",
                "Value": "yes"
            },
            {
                "Key": "C Pillar Lower Trim (Molded)",
                "Value": "yes"
            },
            {
                "Key": "Dual-tone Interiors",
                "Value": "yes"
            },
            {
                "Key": "Silver Accent Inside Door Handles",
                "Value": "yes"
            },
            {
                "Key": "Silver Accent on Center Garnish",
                "Value": "-"
            },
            {
                "Key": "Silver Accent on Louvers",
                "Value": "yes"
            },
            {
                "Key": "Silver Accent on Steering Wheel",
                "Value": "yes"
            }
        ]
    }
]

实现代码（JavaScript） #

先将其中一个数组转换为便于快速查找的映射结构，减少嵌套循环次数，提升匹配效率：

// 转换数组为「顶层Key -> 子项Key+Value集合」的映射
function buildLookupMap(arr) {
  const map = {}
  arr.forEach(group => {
    map[group.Key] = new Set(
      group.Value.map(item => `${item.Key}###${item.Value}`)
    )
  })
  return map
}

// 筛选匹配项
function getMatchedResult(arr1, arr2) {
  const lookupMap = buildLookupMap(arr2)
  return arr1.reduce((res, currentGroup) => {
    const groupKey = currentGroup.Key
    // 顶层Key不匹配则跳过该分组
    if (!lookupMap[groupKey]) return res
    // 筛选子项中Key和Value均一致的条目
    const matchedItems = currentGroup.Value.filter(item => {
      return lookupMap[groupKey].has(`${item.Key}###${item.Value}`)
    })
    // 仅保留有匹配子项的分组
    if (matchedItems.length) {
      res.push({
        Key: groupKey,
        Value: matchedItems
      })
    }
    return res
  }, [])
}

// 调用示例
const result = getMatchedResult(arr1, arr2)
console.log(result)

输出结果 #

注：你提供的预期输出中「Interior」为笔误，实际匹配结果顶层Key与输入保持一致为「Interiors」

[
  {
    "Key": "Exterior",
    "Value": [
      {
        "Key": "Body Coloured Outside Door Handles ",
        "Value": "yes"
      },
      {
        "Key": "Body Side Molding",
        "Value": "-"
      }
    ]
  },
  {
    "Key": "Interiors",
    "Value": [
      {
        "Key": "C Pillar Lower Trim (Molded)",
        "Value": "yes"
      },
      {
        "Key": "Dual-tone Interiors",
        "Value": "yes"
      },
      {
        "Key": "Silver Accent on Center Garnish",
        "Value": "-"
      }
    ]
  }
]

内容的提问来源于stack exchange，提问作者ltech