How to get time (hour, minute, second) in Swift 3 using NSDate?

问题

How can you determine the hour, minute and second from NSDate class in Swift 3?

In Swift 2:

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

Swift 3?

回答1:

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.

回答2:

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)")

回答3:

let date = Date()       
let units: Set<Calendar.Component> = [.hour, .day, .month, .year]
let comps = Calendar.current.dateComponents(units, from: date)

回答4:

Swift 4

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

回答5:

In Swift 3 you can do this,

let date = Date()
let hour = Calendar.current.component(.hour, from: date)

回答6:

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)

回答7:

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

回答8:

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...

回答9:

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

来源：https://stackoverflow.com/questions/38248941/how-to-get-time-hour-minute-second-in-swift-3-using-nsdate

标签

nsdate

swift3