javascript中散列的Group by和sum数组

// 原始数组
const arr = [
  { name: 'apple', category: 'fruit', price: 1 },
  { name: 'banana', category: 'fruit', price: 2 },
  { name: 'carrot', category: 'vegetable', price: 3 },
  { name: 'orange', category: 'fruit', price: 4 },
  { name: 'broccoli', category: 'vegetable', price: 5 }
];

// 使用散列实现Group by和sum数组
const groupByAndSum = (array, key, sumKey) => {
  const hash = {};
  
  array.forEach(item => {
    const keyValue = item[key];
    const sumValue = item[sumKey];
    
    if (!hash[keyValue]) {
      hash[keyValue] = {
        [key]: keyValue,
        [sumKey]: sumValue
      };
    } else {
      hash[keyValue][sumKey] += sumValue;
    }
  });
  
  return Object.values(hash);
};

// 按照category进行Group by，并计算price的总和
const groupedArray = groupByAndSum(arr, 'category', 'price');
console.log(groupedArray);

[
  { category: 'fruit', price: 7 },
  { category: 'vegetable', price: 8 }
]