javascript 中具有深层嵌套对象的数组的交集

Question

我想包含数组中存在的对象的所有键并丢弃其余键， 例如，如果我有一个数组，

const arr = ['apple', 'milk', 'bread', 'coke'];

和一个对象,

const dummy = {
    apple: {
        category: 'fruit'
    },
    banana: {
        category: 'fruit'
    },
    potato: {
        category: 'vegetable'
    },
    dairy: {
        milk: {
          type: 'A2'
        }
    },
    bakery: {
        bread: {
            type: 'brown'
        }
    },
    beverage: {
      cold_drink: {
        coke: {
          type: 'diet'
        },
        beer: {
        }
      }
    }
}

我希望我的结果对象仅包含来自 arr 的键，无论是直接键还是深层嵌套。所以对于上述情况，我的结果对象看起来像，

{
    apple: {
        category: 'fruit'
    },
    dairy: {
        milk: {
          type: 'A2'
        }
    },
    bakery: {
        bread: {
            type: 'brown'
        }
    },
    beverage: {
      cold_drink: {
        coke: {
          type: 'diet'
        },
        beer: {}
      }
    }
}

我正在尝试通过递归解决此问题，但无法正确获得输出。下面是我的代码，你能帮我看看我哪里出错了吗？

function fetchResultantObject(object, key, result) {
  if(typeof object !== 'object')
    return null;
  for(let objKey in object) {
    if(key.indexOf(objKey) > -1) {
      result[objKey] = object[objKey];
    } else {
      result[objKey] = fetchValueByKey(object[objKey], key, result);
    }
  }
  return result;
}

console.log(fetchResultantObject(dummy, arr, {}));

Answer 1

您可以过滤条目并检查（嵌套的）对象是否包含想要的键。

const
    hasKey = object => object
        && typeof object === 'object'
        && (keys.some(k => k in object) || Object.values(object).some(hasKey)),
    keys = ['apple', 'milk', 'bread', 'coke'],
    data = { apple: { category: 'fruit' }, banana: { category: 'fruit' }, potato: { category: 'vegetable' }, dairy: { milk: { type: 'A2' } }, bakery: { bread: { type: 'brown' } }, beverage: { cold_drink: { coke: { type: 'diet' } } } },
    result = Object.fromEntries(Object
        .entries(data)
        .filter(([k, v]) => hasKey({ [k]: v }))
    );

console.log(result);

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javascript 中具有深层嵌套对象的数组的交集

Intersection of an array with a deeply nested object in javascript

javascript

arrays

object

intersection