Question

给出以下对象数组：

  var arrayOfObjs = [{
    id: "d8eed6df-9f12-47d4-5b71-3352a92ebcf0",
    typeID: 2
  },
  {
    id : "270d8355-d8b6-49c4-48ac-97a44422c705",
    typeID: 3
  },
  {
    id : "sdks7878-d8b6-49c4-48ac-97a44422c705",
    typeID: 4
  }];

一堆Ints：

var arrayOfInts = [2, 4];

如果int数组与arrayOfObjects匹配，我如何比较两者并返回一个ID数组。

回报应该是：

var matchingIDs = [
    "d8eed6df-9f12-47d4-5b71-3352a92ebcf0", 
    "sdks7878-d8b6-49c4-48ac-97a44422c705"
];


var missingIDs = ["270d8355-d8b6-49c4-48ac-97a44422c705"];

Answer 1

使用array.prototype.filter，array.prototype.includes和array.prototype.map

＆＃13;

var datas = [{
    id: "d8eed6df-9f12-47d4-5b71-3352a92ebcf0",
    typeID: 2
  },
  {
    id : "270d8355-d8b6-49c4-48ac-97a44422c705",
    typeID: 3
  },
  {
    id : "sdks7878-d8b6-49c4-48ac-97a44422c705",
    typeID: 4
}];

var arrayOfInts = [2, 4];

var matchingIDs = datas.filter(d => arrayOfInts.includes(d.typeID)).map(e => e.id);

var missingIDs= datas.filter(d => !arrayOfInts.includes(d.typeID)).map(e => e.id);

console.log('matchingIDs: ', matchingIDs);
console.log('missingIDs: ', missingIDs);

＆＃13;

Answer 2

实现这一目标的方法很多，我选择了map \ filter用法，因为javascript是一种函数式语言。

const allItems = [{
    id: "d8eed6df-9f12-47d4-5b71-3352a92ebcf0",
    typeID: 2
  },
  {
    id : "270d8355-d8b6-49c4-48ac-97a44422c705",
    typeID: 3
  },
  {
    id : "sdks7878-d8b6-49c4-48ac-97a44422c705",
    typeID: 4
  }];

const validIds = [2, 4];

const filteredItems = allItems
                      .filter(({typeID})=> validIds.includes(typeID))
                      .map(({id})=>id)

console.log(filteredItems)

Answer 3

使用lodash，您可以使用包含_.keyBy()，_.at()和_.map()的链来实现此目的：

var arrayOfObjs = [{"id":"d8eed6df-9f12-47d4-5b71-3352a92ebcf0","typeID":2},{"id":"270d8355-d8b6-49c4-48ac-97a44422c705","typeID":3},{"id":"sdks7878-d8b6-49c4-48ac-97a44422c705","typeID":4}];

var arrayOfInts = [2, 4];

var result = _(arrayOfObjs)
  .keyBy('typeID') // get a dictionary of objects by their type ids
  .at(arrayOfInts) // get the objects that matches the array of ints
  .map('id') // map each object to the id
  .value();
  
console.log(result);

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.4/lodash.min.js"></script>

将int数组与Array of Objects和return属性进行比较

3 个答案: