根据公用值对数组进行分组

function groupBy(arr, key) {
  const groups = {};
  arr.forEach(element => {
    const groupKey = element[key];
    if (!groups[groupKey]) {
      groups[groupKey] = [];
    }
    groups[groupKey].push(element);
  });
  return groups;
}

// 示例用法
const data = [
  { name: 'Alice', age: 25, gender: 'female' },
  { name: 'Bob', age: 30, gender: 'male' },
  { name: 'Charlie', age: 25, gender: 'male' },
  { name: 'Diana', age: 30, gender: 'female' }
];

const groupedData = groupBy(data, 'age');
console.log(groupedData);

{
  25: [
    { name: 'Alice', age: 25, gender: 'female' },
    { name: 'Charlie', age: 25, gender: 'male' }
  ],
  30: [
    { name: 'Bob', age: 30, gender: 'male' },
    { name: 'Diana', age: 30, gender: 'female' }
  ]
}