如何使用NSDate在Swift 3中获取时间(小时,分钟,秒)？

Question

如何确定Swift 3中NSDate类的小时,分​​钟和秒？

在Swift 2中:

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

斯威夫特3？

Answer 1

在Swift 3.0中, Apple删除了"NS"前缀并使一切变得简单.以下是从'Date'类获取小时,分钟和秒的方法(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)")

像这些你可以通过相应的方式获得时代,年,月,日期等.

Answer 2

Swift 3.0

// *** 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)")

Answer 3

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

Answer 4

斯威夫特4

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

Answer 5

在Swift 3中你可以这样做,

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

Answer 6

斯威夫特 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)
    }
}

用法：

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

Answer 7

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)

Answer 8

对于那些想要在多个类中使用当前日期的人来说，这可能很方便。

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
    }
}

用法

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