比較兩個物件陣列，如果物件值相等則洗掉

我已經嘗試在這里修改一些類似的解決方案，但我一直卡住，我相信我已經弄清楚了其中的一部分，但主要的警告是：

一些物件有額外的鍵，這使得我的物件比較邏輯無用。

我正在嘗試比較兩個物件陣列。一個陣列是原始陣列，另一個陣列包含我想從原始陣列中洗掉的專案。但是還有一個額外的問題，即第二個陣列包含額外的鍵，所以我的比較邏輯不起作用。

一個例子會使這更容易，假設我有以下兩個陣列：

const originalArray = [{id: 1, name: "darnell"}, {id: 2, name: "funboi"}, 
{id: 3, name: "jackson5"}, {id: 4, name: "zelensky"}];

const itemsToBeRemoved = [{id: 2, name: "funboi", extraProperty: "something"}, 
{id: 4, name: "zelensky", extraProperty: "somethingelse"}];

運行邏輯后，我的最終輸出應該是這個陣列：

[{id: 1, name: "darnell"}, {id: 3, name: "jackson5"}]

這是我擁有的當前代碼/邏輯，它比較但不處理額外的鍵。我該如何處理？先感謝您。

const prepareArray = (arr) => {
  return arr.map((el) => {
    if (typeof el === "object" && el !== null) {
      return JSON.stringify(el);
    } else {
      return el;
    }
  });
};

const convertJSON = (arr) => {
  return arr.map((el) => {
    return JSON.parse(el);
  });
};

const compareArrays = (arr1, arr2) => {
  const currentArray = [...prepareArray(arr1)];
  const deletedItems = [...prepareArray(arr2)];
  const compared = currentArray.filter((el) => deletedItems.indexOf(el) === -1);
  return convertJSON(compared);
};

uj5u.com熱心網友回復：

使用filterand怎么樣some？您可以使用 擴展選擇屬性的過濾條件&&。

const originalArray = [
  { id: 1, name: 'darnell' },
  { id: 2, name: 'funboi' },
  { id: 3, name: 'jackson5' },
  { id: 4, name: 'zelensky' },
];
const itemsToBeRemoved = [
  { id: 2, name: 'funboi', extraProperty: 'something' },
  { id: 4, name: 'zelensky', extraProperty: 'somethingelse' },
];
console.log(
  originalArray.filter(item => !itemsToBeRemoved.some(itemToBeRemoved => itemToBeRemoved.id === item.id))
)

或者你也可以概括它。

const originalArray = [
  { id: 1, name: 'darnell' },
  { id: 2, name: 'funboi' },
  { id: 3, name: 'jackson5' },
  { id: 4, name: 'zelensky' },
];
const itemsToBeRemoved = [
  { id: 2, name: 'funboi', extraProperty: 'something' },
  { id: 4, name: 'zelensky', extraProperty: 'somethingelse' },
];
function filterIfSubset(originalArray, itemsToBeRemoved) {
  const filteredArray = [];
  for (let i = 0; i < originalArray.length; i  ) {
    let isSubset = false;
    for (let j = 0; j < itemsToBeRemoved.length; j  ) {
      // check if whole object is a subset of the object in itemsToBeRemoved
      if (Object.keys(originalArray[i]).every(key => originalArray[i][key] === itemsToBeRemoved[j][key])) {
        isSubset = true;
      }
    }
    if (!isSubset) {
      filteredArray.push(originalArray[i]);
    }
  }
  return filteredArray;
}
console.log(filterIfSubset(originalArray, itemsToBeRemoved));

第二種方法的另一個更簡單的變體：

const originalArray = [
  { id: 1, name: 'darnell' },
  { id: 2, name: 'funboi' },
  { id: 3, name: 'jackson5' },
  { id: 4, name: 'zelensky' },
];
const itemsToBeRemoved = [
  { id: 2, name: 'funboi', extraProperty: 'something' },
  { id: 4, name: 'zelensky', extraProperty: 'somethingelse' },
];
const removeSubsetObjectsIfExists = (originalArray, itemsToBeRemoved) => {
  return originalArray.filter(item => {
    const isSubset = itemsToBeRemoved.some(itemToBeRemoved => {
      return Object.keys(item).every(key => {
        return item[key] === itemToBeRemoved[key];
      });
    });
    return !isSubset;
  });
}
console.log(removeSubsetObjectsIfExists(originalArray, itemsToBeRemoved));

uj5u.com熱心網友回復：

下面的示例是一個可重用的函式，第三個引數是您比較兩個陣列中的值的鍵。

細節在例子中注釋

const arr=[{id:1,name:"darnell"},{id:2,name:"funboi"},{id:3,name:"jackson5"},{id:4,name:"zelensky"}],del=[{id:2,name:"funboi",extraProperty:"something"},{id:4,name:"zelensky",extraProperty:"somethingelse"}];

/** Compare arrayA vs. delArray by a given key's value.
--- ex. key = 'id'
**/
function deleteByKey(arrayA, delArray, key) {
  /* Get an array of only the values of the given key from delArray
  --- ex. delList = [1, 2, 3, 4]
  */
  const delList = delArray.map(obj => obj[key]);
  
  /* On every object of arrayA compare delList values vs 
 current object's key's value
  --- ex. current obj[id] = 2
  --- [1, 2, 3, 4].includes(obj[id])
  Any match returns an empty array and non-matches are returned 
  in it's own array.
  --- ex. ? [] : [obj]
  The final return is a flattened array of the non-matching objects
  */
  return arrayA.flatMap(obj => delList.includes(obj[key]) ? [] : [obj]);  
};

console.log(deleteByKey(arr, del, 'id'));

標籤：javascript 数组 功能 目的 javascript 对象

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