我正在尝试计算宠物存活的周数和天数。我正在为此使用 SwiftDate。所以我让用户选择生日并将其与当前日期进行比较。
我不想比较时间...所以生日和当前日期应该是同一时间。
我的代码是:
let greg = Calendar(identifier: .gregorian)
var date1 = birthday // from datepicker
var date2 = Date()
var components1 = greg.dateComponents([.year, .month, .day, .hour, .minute, .second], from: date1)
var components2 = greg.dateComponents([.year, .month, .day, .hour, .minute, .second], from: date2)
components1.hour = 15
components1.minute = 0
components1.second = 0
components2.hour = 15
components2.minute = 0
components2.second = 0
date1 = greg.date(from: components1)!
date2 = greg.date(from: components2)!
let daysAlive = (date2 - date1).in(.day)
let weeksAlive = Int(weeksAlive! / 7)
let restDays = daysAlive! - (weeksAlive * 7)
let aLive = "Age: \(weeksAlive) wk, \(restDays) d (\(daysAlive!) d)"
输出是“年龄:28周,3天(199天)”
代码有效……但我该如何重构它?是否有更简单的方法来为两个给定日期设置“同一时间”?
最佳答案
要忽略时间,只需省略 .hour
、.minute
和 .second
的组件即可
let components1 = greg.dateComponents([.year, .month, .day], from: date1)
let components2 = greg.dateComponents([.year, .month, .day], from: date2)
date1 = greg.date(from: components1)!
date2 = greg.date(from: components2)!
这是一个没有任何第三方库的更简单的解决方案。它使用 Calendar
方法 dateComponents( :from:to:
。不需要额外的数学运算。
let greg = Calendar(identifier: .gregorian)
var date1 = greg.date(from: DateComponents(year: 2017, month: 6, day: 25))!
var date2 = Date()
var components1 = greg.dateComponents([.year, .month, .day], from: date1)
var components2 = greg.dateComponents([.year, .month, .day], from: date2)
let weeksAndDays = greg.dateComponents([.weekOfMonth, .day], from: components1, to: components2)
let justDays = greg.dateComponents([.day], from: components1, to: components2)
let aLive = "Age: \(weeksAndDays.weekOfMonth!) wk, \(weeksAndDays.day!) d (\(justDays.day!) d)"
// "Age: 28 wk, 3 d (199 d)"
关于SwiftDate 和日期计算,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/48196304/