如何用静态时间计算当前时间和昨天日期之间的时间差

Question

我有一个当前时间和一个静态时间（例如 - 昨天晚上9.30时），我需要找出这两个时间之间的时差，以hh：mm： ss格式。

这是我用来获取当前时间的代码：

let date = Date() 
let calendar = Calendar.current 

let hour = calendar.component(.hour, from: date) 
let minutes = calendar.component(.minute, from: date) 
let seconds = calendar.component(.second, from: date) 
print("hours = \(hour):\(minutes):\(seconds)") 

Answer 1

试试这个： -

let dateFormatter = DateFormatter() 
    var userCalendar = Calendar.current 
    userCalendar.timeZone = TimeZone.current 
    let requestedComponent: Set<Calendar.Component> = [.hour,.minute,.second] 
    dateFormatter.dateFormat = "dd/MM/yy hh:mm:ss" 
    let startTime = Date() 
    let endTime = dateFormatter.date(from: "28/08/17 08:40:00") 
    let timeDifference = userCalendar.dateComponents(requestedComponent, from: endTime!, to: startTime) 
    print(timeDifference) 
    let date = Calendar(identifier: .gregorian).date(from: timeDifference) 
    dateFormatter.dateFormat = "HH:mm:ss" 
    let dateString = dateFormatter.string(from: date!) 

    print(dateString) 

您可以根据您的要求更改格式。

Answer 2

let date = Date() 
let cal = Calendar.current 
let formatter = DateFormatter() 
formatter.dateFormat = "HH:mm:ss" 
let staticTime = ... 
let comps = cal.dateComponents([.hour, .minute, .second], from: date, to: staticTime) 
let diff = cal.date(from: comps)! 
let diffString = formatter.string(from: diff)