从操场开始。我正在尝试创建一个简单的应用程序。
我创建了一个date对象,就像这样:
var date = NSDate()
我怎样才能得到当前的时间?在其他语言中,我可以这样做:
var hour = date.hour
但我找不到任何这样的属性/方法。我找到了一个方法,dateWithCalendarFormat。我应该用这个吗?如果是,怎么做?
从操场开始。我正在尝试创建一个简单的应用程序。
我创建了一个date对象,就像这样:
var date = NSDate()
我怎样才能得到当前的时间?在其他语言中,我可以这样做:
var hour = date.hour
但我找不到任何这样的属性/方法。我找到了一个方法,dateWithCalendarFormat。我应该用这个吗?如果是,怎么做?
当前回答
仅用于特定格式的日期
let dateFormatter1 = NSDateFormatter()
dateFormatter1.dateStyle = .MediumStyle
dateFormatter1.timeStyle = .NoStyle
dateFormatter1.dateFormat = "dd-MM-yyyy"
let date = dateFormatter1.stringFromDate(NSDate())
其他回答
你可以试试这个
func getTime() -> (hour:Int, min:Int, sec:Int) {
let currentDateTime = NSDate()
let calendar = NSCalendar.currentCalendar()
let components = calendar.components([.Hour,.Minute,.Second], fromDate: currentDateTime)
let hour = components.hour
let min = components.minute
let sec = components.second
return (hour,min,sec)
}
现在调用该方法并接收带有小时、分钟和秒的日期
let currentTime = self.getTime()
print("Hour: \(currentTime.hour) Min: \(currentTime.min) Sec: \(currentTime.sec))")
仅用于特定格式的日期
let dateFormatter1 = NSDateFormatter()
dateFormatter1.dateStyle = .MediumStyle
dateFormatter1.timeStyle = .NoStyle
dateFormatter1.dateFormat = "dd-MM-yyyy"
let date = dateFormatter1.stringFromDate(NSDate())
你也可以使用NSDateFormatter的方便方法,例如:
func printTimestamp() {
let timestamp = NSDateFormatter.localizedStringFromDate(NSDate(), dateStyle: .MediumStyle, timeStyle: .ShortStyle)
print(timestamp)
}
printTimestamp() // Prints "Sep 9, 2014, 4:30 AM"
扩展noiiv的史诗般的简洁解决方案,这里是更简洁的Swift 3/4实现:
斯威夫特3/4
let components = Calendar.current.dateComponents([.hour, .minute], from: Date())
let (hour, minute) = (components.hour, components.minute)
同时,扩展Leo Dabus的扩展,我们可以有:
extension Date {
func components(_ components: Set<Calendar.Component>) -> DateComponents {
return Calendar.current.dateComponents(components, from: self)
}
func component(_ component: Calendar.Component) -> Int {
return Calendar.current.component(component, from: self)
}
var era: Int { return component(.era) }
var year: Int { return component(.year) }
var month: Int { return component(.month) }
var day: Int { return component(.day) }
var hour: Int { return component(.hour) }
var minute: Int { return component(.minute) }
var second: Int { return component(.second) }
var weekday: Int { return component(.weekday) }
var weekdayOrdinal: Int { return component(.weekdayOrdinal) }
var quarter: Int { return component(.quarter) }
var weekOfMonth: Int { return component(.weekOfMonth) }
var weekOfYear: Int { return component(.weekOfYear) }
var yearForWeekOfYear: Int { return component(.yearForWeekOfYear) }
var nanosecond: Int { return component(.nanosecond) }
var calendar: Calendar? { return components([.calendar]).calendar }
var timeZone: TimeZone? { return components([.timeZone]).timeZone }
}
像这样使用它:
let date = Date()
let (hour, minute) = (date.hour, date.minute)
斯威夫特4:
extension Date
{
func hour() -> Int
{
//Get Hour
let calendar = Calendar.current
let components = calendar.component(.hour, from: self)
let hour = components
//Return Hour
return hour
}
func minute() -> Int
{
//Get Minute
let calendar = Calendar.current
let components = calendar.component(.minute, from: self)
let minute = components
//Return Minute
return minute
}
}