根据子数组唯一值获取值

Question

我的JSON 数据如下所示：

{
    "data": [{
            "id": "1",
            "blogTitle": "How to plant a tree?",
            "categories": [{
                "CategoryID": "10",
                "CategoryTitle": "Apple Tree"
            }, {
                "CategoryID": "11",
                "CategoryTitle": "Mango Tree"
            }, {
                "CategoryID": "42",
                "CategoryTitle": "Banana Tree"
            }]
        },
        {
            "id": "2",
            "blogTitle": "How to make Juice?",
            "categories": [{
                "CategoryID": "71",
                "CategoryTitle": "Apple Juice"
            }, {
                "CategoryID": "72",
                "CategoryTitle": "Mango Juice"
            }, {
                "CategoryID": "73",
                "CategoryTitle": "Banana Juice"
            }]

        }
    ]
}

我想要的是通过传递CategoryID的值来获得id的值

例如：如果我发送10，那么我应该得到1 作为回报，因为"CategoryID": "10" 与"id": "1" 在同一块中

每个CategoryID 都是唯一的，从而导致id 的唯一值

我做了什么？

• 我想出的最接近的方法是使用array.filter()，但我能够过滤id 值，给出id 的值，但是我如何获得id 的值，给定CategoryID

有人可以帮帮我吗？

Answer 1

你可以整合你的数据，然后像这样使用Array#some。

const yourObject = {"data":[{"id":"1","blogTitle":"How to plant a tree?","categories":[{"CategoryID":"10","CategoryTitle":"Apple Tree"},{"CategoryID":"11","CategoryTitle":"Mango Tree"},{"CategoryID":"42","CategoryTitle":"Banana Tree"}]},{"id":"2","blogTitle":"How to make Juice?","categories":[{"CategoryID":"71","CategoryTitle":"Apple Juice"},{"CategoryID":"72","CategoryTitle":"Mango Juice"},{"CategoryID":"73","CategoryTitle":"Banana Juice"}]}]};

const find_ID_BasedOn_GivenCategoryId = (categoryId) => {
  for(const item of yourObject.data){
    if(item.categories && item.categories.some(r => r.CategoryID == categoryId))
      return item.id;
  }
  
  return "Not found";
}

console.log(find_ID_BasedOn_GivenCategoryId(11));
console.log(find_ID_BasedOn_GivenCategoryId(71));
console.log(find_ID_BasedOn_GivenCategoryId(999));

更简单的方法： 使用Array#find

const yourObject = {"data":[{"id":"1","blogTitle":"How to plant a tree?","categories":[{"CategoryID":"10","CategoryTitle":"Apple Tree"},{"CategoryID":"11","CategoryTitle":"Mango Tree"},{"CategoryID":"42","CategoryTitle":"Banana Tree"}]},{"id":"2","blogTitle":"How to make Juice?","categories":[{"CategoryID":"71","CategoryTitle":"Apple Juice"},{"CategoryID":"72","CategoryTitle":"Mango Juice"},{"CategoryID":"73","CategoryTitle":"Banana Juice"}]}]};

const find_ID_BasedOn_GivenCategoryId = (categoryId) => {
  const result = yourObject.data.find(item => 
                item.categories && item.categories.some(r => r.CategoryID == categoryId));
  
 return result ? result.id : "Not found"; 
}

console.log(find_ID_BasedOn_GivenCategoryId(11));
console.log(find_ID_BasedOn_GivenCategoryId(71));
console.log(find_ID_BasedOn_GivenCategoryId(999));

Answer 2

您可以使用find 与some 的组合来检查您想要的categoryID，例如：

const data = {
    "data": [{
            "id": "1",
            "blogTitle": "How to plant a tree?",
            "categories": [{
                "CategoryID": "10",
                "CategoryTitle": "Apple Tree"
            }, {
                "CategoryID": "11",
                "CategoryTitle": "Mango Tree"
            }, {
                "CategoryID": "42",
                "CategoryTitle": "Banana Tree"
            }]
        },
        {
            "id": "2",
            "blogTitle": "How to make Juice?",
            "categories": [{
                "CategoryID": "71",
                "CategoryTitle": "Apple Juice"
            }, {
                "CategoryID": "72",
                "CategoryTitle": "Mango Juice"
            }, {
                "CategoryID": "73",
                "CategoryTitle": "Banana Juice"
            }]

        }
    ]
};


const findId = (categoryID, { data }) => {
    const foundItem = data.find(({ categories }) => 
      categories.some(({ CategoryID }) => CategoryID == categoryID)
    );
    return foundItem ? foundItem.id : null;
}

console.log(findId(71, data))

Answer 3

找到+一些

var data = [
  {
    id: "1",
    blogTitle: "How to plant a tree?",
    categories: [
      {
        CategoryID: "10",
        CategoryTitle: "Apple Tree"
      },
      {
        CategoryID: "11",
        CategoryTitle: "Mango Tree"
      },
      {
        CategoryID: "42",
        CategoryTitle: "Banana Tree"
      }
    ]
  },
  {
    id: "2",
    blogTitle: "How to make Juice?",
    categories: [
      {
        CategoryID: "71",
        CategoryTitle: "Apple Juice"
      },
      {
        CategoryID: "72",
        CategoryTitle: "Mango Juice"
      },
      {
        CategoryID: "73",
        CategoryTitle: "Banana Juice"
      }
    ]
  }
];

const findId = (id) => {
  return data?.find((item) =>
    item?.categories?.some((i) => i?.CategoryID === id)
  )?.id;
};


console.log(findId("10")); //1