Javascript 按 2 个属性对数组进行排序和过滤

Question

I want to keep a list of the highest scores by date:

ie

Name: Player A | Score: 2000 | Date: 2020-04-15

Name: Player B| Score: 2001 | Date: 2020-04-16

However i sometimes get a greater score but lower date:

Name: Player A| Score: 2000 | Date: 2020-01-12

Name: Player B| Score: 2001 | Date: 2019-12-20

// should only return: a and c in order.
let arr = [
{name: c, score: 6, date: 5-20-2021},
{name: b, score: 2, date: 5-20-2020},
{name: a, score: 3, date: 5-20-2019}
]
arr.sort((a, b) => (a.score > b.score) ? 1 : -1)
arr.filter((a, b) => (a.submitted > b.submitted) ? 1 : -1)

Answer 1

filter method provide three arguments:

1. current element
2. index of current element
3. array

Therefore, you try to compare submitted with undefined. If you need to get two element from a sorted array, you can just use splice method

arr.sort((a, b) => b.score - a.score).splice(0, 2)

Answer 2

Just put both conditions when you sort:

 <script> let arr = [ {name: "i", score: 16, date: 2-20-2021}, {name: "h", score: 6, date: 5-25-2021}, {name: "g", score: 6, date: 5-20-2022}, {name: "f", score: 6, date: 5-10-2021}, {name: "e", score: 16, date: 5-20-1021}, {name: "d", score: 6, date: 5-20-2001}, {name: "c", score: 6, date: 5-20-2021}, {name: "b", score: 2, date: 5-20-2020}, {name: "a", score: 3, date: 5-20-2019} ] arr.sort((a, b) => (a.score < b.score) && (a.date < b.date)? 1: -1) console.log(arr) </script>