我如何从NSDate获得小时和分钟？

在我的应用程序中，我需要分别获取小时和分钟：

NSString *currentHour=[string1 substringWithRange: NSMakeRange(0,2)]; int currentHourInNumber=[currentHour intValue]; 

考虑string1包含从11:59:13 AM来的11:59:13 AM 。

在这里，如果我使用上面的代码，它可以得到小时，如果它是大于9.否则我需要更改NSMakeRange(0,1)以获得1至9之间的小时。

有什么方法来获得小时，分钟等？

在此先感谢，请提供示例代码。

Answer 1

使用NSDateFormatter将string1转换为NSDate ，然后获取所需的NSDateComponents ：

Obj-C ：

 NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init]; [dateFormatter setDateFormat:@"<your date format goes here"]; NSDate *date = [dateFormatter dateFromString:string1]; NSCalendar *calendar = [NSCalendar currentCalendar]; NSDateComponents *components = [calendar components:(NSCalendarUnitHour | NSCalendarUnitMinute) fromDate:date]; NSInteger hour = [components hour]; NSInteger minute = [components minute]; 

斯威夫特1和2 ：

 let dateFormatter = NSDateFormatter() dateFormatter.dateFormat = "Your date Format" let date = dateFormatter.dateFromString(string1) let calendar = NSCalendar.currentCalendar() let comp = calendar.components([.Hour, .Minute], fromDate: date) let hour = comp.hour let minute = comp.minute 

Swift 3 ：

 let dateFormatter = DateFormatter() dateFormatter.dateFormat = "Your date Format" let date = dateFormatter.date(from: string1) let calendar = Calendar.current let comp = calendar.dateComponents([.hour, .minute], from: date) let hour = comp.hour let minute = comp.minute 

关于dateformat的更多信息在官方的unicode网站上

Answer 2

如果你只需要它作为一个string呈现，下面的代码更容易

 NSDateFormatter *formatter = [[NSDateFormatter alloc] init]; [formatter setDateFormat:@"HH:mm"]; NSString *startTimeString = [formatter stringFromDate:startTimePicker.date]; 

Answer 3

这在我看来是问题之后，不需要格式化程序：

 NSDate *date = [NSDate date]; NSCalendar *calendar = [NSCalendar currentCalendar]; NSDateComponents *components = [calendar components:(NSCalendarUnitHour | NSCalendarUnitMinute) fromDate:date]; NSInteger hour = [components hour]; NSInteger minute = [components minute]; 

Answer 4

NSDateComponents ，所有你需要的可以在这里find： http : //developer.apple.com/mac/library/documentation/cocoa/Conceptual/DatesAndTimes/Articles/dtCalendars.html

Answer 5

在iOS 8中，Apple引入了一个辅助方法来从NSDate对象中检索hour ， minute ， second和nanosecond 。

Objective-C的

 NSDate *date = [NSDate currentDate]; NSInteger hour = 0; NSInteger minute = 0; NSCalendar *currentCalendar = [NSCalendar currentCalendar]; [currentCalendar getHour:&hour minute:&minute second:NULL nanosecond:NULL fromDate:date]; NSLog(@"the hour is %ld and minute is %ld", (long)hour, (long)minute); 

迅速

 let date = NSDate() var hour = 0 var minute = 0 let calendar = NSCalendar.currentCalendar() if #available(iOS 8.0, *) { calendar.getHour(&hour, minute: &minute, second: nil, nanosecond: nil, fromDate: date) print("the hour is \(hour) and minute is \(minute)") } 

Answer 6

如果你要使用C库，那么可以这样做：

 time_t t; struct tm * timeinfo; time (&t); timeinfo = localtime (&t); NSLog(@"Hour: %d Minutes: %d", timeinfo->tm_hour, timeinfo->tm_min); 

并使用Swift：

 var t = time_t() time(&t) let x = localtime(&t) println("Hour: \(x.memory.tm_hour) Minutes: \(x.memory.tm_min)") 

有关进一步指导，请参阅： http : //www.cplusplus.com/reference/ctime/localtime/

Answer 7

Swift 2.0

  let dateNow = NSDate() let calendar = NSCalendar.currentCalendar() let hour = calendar.component(NSCalendarUnit.Hour, fromDate: dateNow) let minute = calendar.component(NSCalendarUnit.Minute, fromDate: dateNow) print(String(hour)) print(String(minute)) 

请注意在打印语句中将String转换为String，您可以轻松地将该值赋予variables，如下所示：

 var hoursString = String(hour) var minutesString = String(minute) 

然后你可以连接这样的值：

 var compoundString = "\(hour):\(minute)" print(compoundString) 

Answer 8

Swift 2.0

你可以做以下的事情从date中获得小时和分钟：

 let dateFromat = NSDateFormatter() dateFromat.dateFormat = "hh:mm a" let date = dateFromat.dateFromString(string1) // In your case its string1 print(date) // you will get - 11:59 AM