如何将对象数组转换为键值为数组对象

// 原始对象数组
const products = [
  { name: 'Apple', color: 'Red' },
  { name: 'Banana', color: 'Yellow' },
  { name: 'Cherry', color: 'Red' },
  { name: 'Date', color: 'Brown' },
  { name: 'Elderberry', color: 'Purple' }
];

// 转换函数
function groupBy(array, key) {
  return array.reduce((result, item) => {
    (result[item[key]] = result[item[key]] || []).push(item);
    return result;
  }, {});
}

// 使用转换函数
const groupedProducts = groupBy(products, 'color');

console.log(groupedProducts);

{
  Red: [
    { name: 'Apple', color: 'Red' },
    { name: 'Cherry', color: 'Red' }
  ],
  Yellow: [
    { name: 'Banana', color: 'Yellow' }
  ],
  Brown: [
    { name: 'Date', color: 'Brown' }
  ],
  Purple: [
    { name: 'Elderberry', color: 'Purple' }
  ]
}

function groupBy(array, key) {
  return array.reduce((result, item) => {
    const keyValue = item[key];
    if (keyValue !== undefined) { // 检查属性值是否未定义
      (result[keyValue] = result[keyValue] || []).push(item);
    }
    return result;
  }, {});
}