자바스크립트 groupBy()

1 개요

자바스크립트 groupBy()

2 Object.groupBy()

const inventory = [
  { name: "asparagus", type: "vegetables", quantity: 5 },
  { name: "bananas", type: "fruit", quantity: 0 },
  { name: "goat", type: "meat", quantity: 23 },
  { name: "cherries", type: "fruit", quantity: 5 },
  { name: "fish", type: "meat", quantity: 22 },
];
const result = Object.groupBy(inventory, ({ type }) => type);
console.log(result);

3 직접 구현

function groupBy(array, key) {
  return array.reduce((result, currentValue) => {
    const groupKey = currentValue[key];
   if (!result[groupKey]) {
      result[groupKey] = [];
    }
    result[groupKey].push(currentValue);
    return result;
  }, {});
}

const inventory = [
  { name: "asparagus", type: "vegetables", quantity: 5 },
  { name: "bananas", type: "fruit", quantity: 0 },
  { name: "goat", type: "meat", quantity: 23 },
  { name: "cherries", type: "fruit", quantity: 5 },
  { name: "fish", type: "meat", quantity: 22 },
];
const result = groupBy(inventory, 'type');
console.log(result);

4 같이 보기

• 자바스크립트 reduce()
• 함수 groupBy()

5 참고

• https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/groupBy