如何获得时间(小时，分钟，秒)在 Swift 3使用 NSDate？

在 Swift 3中如何确定 NSDate 课程的小时、分钟和秒数？

在 Swift 2中:

let date = NSDate()
let calendar = NSCalendar.currentCalendar()
let components = calendar.components(.Hour, fromDate: date)
let hour = components.hour

Swift 3？

161246 次浏览
小开

In Swift 3.0 Apple removed 'NS' prefix and made everything simple. Below is the way to get hour, minute and second from 'Date' class (NSDate alternate)

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)")

Like these you can get era, year, month, date etc. by passing corresponding.

小开

Swift 4.2 & 5

// *** Create date ***
let date = Date()


// *** create calendar object ***
var calendar = Calendar.current


// *** Get components using current Local & Timezone ***
print(calendar.dateComponents([.year, .month, .day, .hour, .minute], from: date))


// *** define calendar components to use as well Timezone to UTC ***
calendar.timeZone = TimeZone(identifier: "UTC")!


// *** Get All components from date ***
let components = calendar.dateComponents([.hour, .year, .minute], from: date)
print("All Components : \(components)")


// *** Get Individual components from date ***
let hour = calendar.component(.hour, from: date)
let minutes = calendar.component(.minute, from: date)
let seconds = calendar.component(.second, from: date)
print("\(hour):\(minutes):\(seconds)")

Swift 3.0

// *** Create date ***
let date = Date()


// *** create calendar object ***
var calendar = NSCalendar.current


// *** Get components using current Local & Timezone ***
print(calendar.dateComponents([.year, .month, .day, .hour, .minute], from: date as Date))


// *** define calendar components to use as well Timezone to UTC ***
let unitFlags = Set<Calendar.Component>([.hour, .year, .minute])
calendar.timeZone = TimeZone(identifier: "UTC")!


// *** Get All components from date ***
let components = calendar.dateComponents(unitFlags, from: date)
print("All Components : \(components)")


// *** Get Individual components from date ***
let hour = calendar.component(.hour, from: date)
let minutes = calendar.component(.minute, from: date)
let seconds = calendar.component(.second, from: date)
print("\(hour):\(minutes):\(seconds)")
小开

In Swift 3 you can do this,

let date = Date()
let hour = Calendar.current.component(.hour, from: date)
小开 
let date = Date()
let units: Set<Calendar.Component> = [.hour, .day, .month, .year]
let comps = Calendar.current.dateComponents(units, from: date)
小开 
let hours = time / 3600
let minutes = (time / 60) % 60
let seconds = time % 60
return String(format: "%0.2d:%0.2d:%0.2d", hours, minutes, seconds)
小开 
swift 4


==> Getting iOS device current time:-


print(" ---> ",(Calendar.current.component(.hour, from: Date())),":",
(Calendar.current.component(.minute, from: Date())),":",
(Calendar.current.component(.second, from: Date())))


output: ---> 10 : 11: 34
小开

Swift 4

    let calendar = Calendar.current
let time=calendar.dateComponents([.hour,.minute,.second], from: Date())
print("\(time.hour!):\(time.minute!):\(time.second!)")
小开

For best useful I create this function:

func dateFormatting() -> String {
let date = Date()
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "EEEE dd MMMM yyyy - HH:mm:ss"//"EE" to get short style
let mydt = dateFormatter.string(from: date).capitalized


return "\(mydt)"
}

You simply call it wherever you want like this:

print("Date = \(self.dateFormatting())")

this is the Output:

Date = Monday 15 October 2018 - 17:26:29

if want only the time simply change :

dateFormatter.dateFormat  = "HH:mm:ss"

and this is the output:

Date = 17:27:30

and that's it...

小开

This might be handy for those who want to use the current date in more than one class.

extension String {


func  getCurrentTime() -> String {
    

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

let year = calendar.component(.year, from: date)
let month = calendar.component(.month, from: date)
let day = calendar.component(.day, from: date)
let hour = calendar.component(.hour, from: date)
let minutes = calendar.component(.minute, from: date)
let seconds = calendar.component(.second, from: date)
    

let realTime = "\(year)-\(month)-\(day)-\(hour)-\(minutes)-\(seconds)"
    

return realTime
}
}

Usage

var time = ""
time = time.getCurrentTime()
print(time)   // 1900-12-09-12-59
小开

Swift 5+

extension Date {
    

func get(_ type: Calendar.Component)-> String {
let calendar = Calendar.current
let t = calendar.component(type, from: self)
return (t < 10 ? "0\(t)" : t.description)
}
}

Usage:

print(Date().get(.year)) // => 2020
print(Date().get(.month)) // => 08
print(Date().get(.day)) // => 18
小开

Swift 5+ Date extension to get Int value of any desired date component:

extension Date {
func component(_ component: Calendar.Component) -> Int {
Calendar.current.component(component, from: self)
}
}

Usage:

let now = Date()
print(now.component(.year))  // 2021
print(now.component(.month)) // 12
print(now.component(.day))   // 30

提交答案