对象数组最近的日期

Question

var dateArray = ['11/01/2020', '10/01/2020', '09/01/2020', '07/01/2020', '06/01/2020']

如果我有一个日期08/01/2020，那么我需要在数组中找到它之前最近的日期07/01/2020。我省略了时间，但这也是日期的一部分。

Answer 1

var dateArray = ['11/01/2020', '10/01/2020', '09/01/2020', '07/01/2020', '06/01/2020']
let date = '08/01/2020'
function findClosestPrevDate(arr,target){
let targetDate = new Date(target);
let previousDates = arr.filter(e => ( targetDate  - new Date(e)) > 0)
let sortedPreviousDates =  previousDates.filter((a,b) => new Date(a) - new Date(b))
return sortedPreviousDates[0] || null
}
let r1 = findClosestPrevDate(dateArray,"08/01/2020")
console.log(r1)
let r2 = findClosestPrevDate(dateArray,"10/01/2020")
console.log(r2)