仅当键匹配时才合并 2 个对象数组

Question

我有 2 个对象数组，只有当两个数组的 user 匹配时，我才想将它们的属性合并在一起。

示例数组

arr1 = [{ bank: 1, user: 'fred', depositAmount: 100, withdrawalAmount: 0 }];
arr2 = [{ user: 'fred', gender: 'male', age: 27, state: "arizona" }, { user: 'john',gender: 'male', age: 28, state: "texas" }];

预期输出

arr1 = [{ bank: 1, user: 'fred', depositAmount: 100, withdrawalAmount: 0, gender: 'male', age: 27, state: "arizona" }];

到目前为止，这是我尝试过的方法，但它返回的是一个空数组

var result = [];
arr1.concat(arr2)
  .forEach(item =>
    result[item.user] =
    Object.assign({}, result[item.user], item)
  );
result = result.filter(r => r);
console.log(result)

Answer 1

您可以通过使用 map、filter 数组功能和 spread operator (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Spread_syntax):

来实现

const arr1 = [{ bank: 1, user: 'fred', depositAmount: 100, withdrawalAmount: 0 }, { user: 'john2',gender: 'male', age: 28, state: "texas" }];
const arr2 = [{ user: 'fred', gender: 'male', age: 27, state: "arizona" }, { user: 'john',gender: 'male', age: 28, state: "texas" }];
const newArray = arr1.map((obj) => {
  const secondArrayObj = arr2.find((obj2) => obj2.user === obj.user);
  if (secondArrayObj) {
    return {...secondArrayObj, ...obj}
  }
  return null;
}).filter((obj) => obj != null);
console.log(newArray); 
//[{
//  "user": "fred",
//  "gender": "male",
//  "age": 27,
//  "state": "arizona",
//  "bank": 1,
//  "depositAmount": 100,
//  "withdrawalAmount": 0
//}]

请注意，如果您在两个对象中有相同的字段，来自 arr2 对象的字段将被来自 arr1 对象的字段覆盖

仅当键匹配时才合并 2 个对象数组

Merge 2 array of objects only if key matches

arrays

typescript

object