從陣列中獲取5個最舊的物件

我有一個形式的物件陣列：

{productID: '15', name: 'Pepsi', category: 'food/beverages', dateAdded: '2015-12-21T17:42:34Z'}

我想通過比較dateAdded字串來找到 5 個最舊的專案。我嘗試了一些低效的回圈并失敗了reduce()，但我覺得有一種更有效的方法。如何累積 5 個最舊的專案？

uj5u.com熱心網友回復：

一個簡單的排序/切片就可以了——日期的格式意味著你可以localeCompare在你的排序呼叫中做一個 ...`

const array = [
    {productID: '15',name: 'Pepsi',category: 'food/beverages',dateAdded: '2015-12-21T17:42:34Z'},
    {productID: '13',name: 'Coke',category: 'food/beverages',dateAdded: '2015-12-20T17:42:34Z'}
];
const top5 = array
    .sort(({dateAdded: a}, {dateAdded: b}) => a.localeCompare(b))
    .slice(0, 5);
console.log(top5);

uj5u.com熱心網友回復：

對專案進行排序，dateAdded然后取前 5 個，這應該是最舊的

uj5u.com熱心網友回復：

按日期時間排序

const array = [
  { productID: '0', name: 'Pepsi', category: 'food/beverages', dateAdded: '2015-12-21T17:42:34Z' },
  { productID: '1', name: 'Coke', category: 'food/beverages', dateAdded: '2015-10-20T17:42:34Z' },
  { productID: '2', name: 'Coke', category: 'food/beverages', dateAdded: '2015-11-20T17:42:34Z' },
  { productID: '3', name: 'Coke', category: 'food/beverages', dateAdded: '2015-08-20T17:42:34Z' },
  { productID: '4', name: 'Coke', category: 'food/beverages', dateAdded: '2015-01-20T17:42:34Z' },
  { productID: '5', name: 'Coke', category: 'food/beverages', dateAdded: '2015-03-20T17:42:34Z' },
  { productID: '6', name: 'Coke', category: 'food/beverages', dateAdded: '2016-10-20T17:42:34Z' },
  { productID: '7', name: 'Coke', category: 'food/beverages', dateAdded: '2017-10-20T17:42:34Z' },
];

const newArr = array.sort((firstEl, secondEl) => new Date(firstEl.dateAdded).getTime() - new Date(secondEl.dateAdded).getTime()).slice(0, 5)

console.log(newArr)

uj5u.com熱心網友回復：

const oldest = (arr) => arr.sort((a, b) => new Date(a.dateAdded) - new Date(b.dateAdded)).slice(0, 5)
const products = [
  { productID: '15', name: 'Pepsi', category: 'food/beverages', dateAdded: '2015-12-21T17:42:34Z' },
  { productID: '16', name: 'Coke', category: 'food/beverages', dateAdded: '2015-12-21T17:42:34Z' },
  { productID: '17', name: 'Sprite', category: 'food/beverages', dateAdded: '2014-12-21T17:42:34Z' },
  { productID: '18', name: 'Fanta', category: 'food/beverages', dateAdded: '2015-12-21T17:42:34Z' },
  { productID: '19', name: 'Dr Pepper', category: 'food/beverages', dateAdded: '2015-12-21T17:42:34Z' },
  { productID: '20', name: 'Mountain Dew', category: 'food/beverages', dateAdded: '2012-12-21T17:42:34Z' },
  { productID: '21', name: 'Diet Coke', category: 'food/beverages', dateAdded: '2015-12-21T17:42:34Z' },
  { productID: '22', name: '7up', category: 'food/beverages', dateAdded: '2015-12-21T17:42:34Z' },
  { productID: '23', name: 'Cherry Coke', category: 'food/beverages', dateAdded: '2015-12-21T17:42:34Z' },
  { productID: '24', name: 'Cherry Coke Zero', category: 'food/beverages', dateAdded: '2010-12-21T17:42:34Z' },
  { productID: '25', name: 'Cherry Coke Diet', category: 'food/beverages', dateAdded: '2015-12-21T17:42:34Z' },
  { productID: '26', name: 'Cherry Coke Diet Zero', category: 'food/beverages', dateAdded: '2015-12-21T17:42:34Z' },
  { productID: '27', name: 'Cherry Coke Diet Zero', category: 'food/beverages', dateAdded: '2015-12-21T17:42:34Z' },
  { productID: '28', name: 'Cherry Coke Diet Zero', category: 'food/beverages', dateAdded: '2011-12-21T17:42:34Z' },
  { productID: '29', name: 'Cherry Coke Diet Zero', category: 'food/beverages', dateAdded: '2015-12-21T17:42:34Z' },
  { productID: '30', name: 'Cherry Coke Diet Zero', category: 'food/beverages', dateAdded: '2014-12-21T17:42:34Z' }]
console.log(oldest(products));

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