swift3 - 如何在 swift 3.0 中比较日期？

Question

我有两个日期，我想比较一下。
如何比较日期？
我必须约会对象。说modificateionDate较旧的 updatedDate .

那么比较日期的最佳做法是什么？

Answer 1

根据@NiravD 的回答，Date是 Comparable .但是，如果要与给定粒度进行比较，可以使用 Calendar的compare(_:to:toGranularity:)
例子…

let dateRangeStart = Date()
let dateRangeEnd = Date().addingTimeInterval(1234)

// Using granularity of .minute
let order = Calendar.current.compare(dateRangeStart, to: dateRangeEnd, toGranularity: .minute)

switch order {
case .orderedAscending:
    print("\(dateRangeEnd) is after \(dateRangeStart)")
case .orderedDescending:
    print("\(dateRangeEnd) is before \(dateRangeStart)")
default:
    print("\(dateRangeEnd) is the same as \(dateRangeStart)")
}

> 2017-02-17 10:35:48 +0000 is after 2017-02-17 10:15:14 +0000

// Using granularity .hour
let order = Calendar.current.compare(dateRangeStart, to: dateRangeEnd, toGranularity: .hour)

> 2017-02-17 10:37:23 +0000 is the same as 2017-02-17 10:16:49 +0000