我如何從 NSDate 獲取小時和分鍾？

Question

在我的應用程序中，我需要分別獲取小時和分鍾：

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

考慮string1包含來自 datepicker 的11:59:13 AM 。

在這里，如果我使用上面的代碼，如果它大於 9，則可以獲取小時。否則我需要更改NSMakeRange(0,1)以獲取 1 到 9 之間的小時。

有沒有什么方法可以獲取小時、分鍾等？

請提供示例代碼。

Answer 1

使用NSDateFormatter將string1轉換為NSDate ，然后獲取所需的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];

Swift 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

斯威夫特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

有關dateformat的更多信息，請訪問官方unicode網站

Answer 2

如果您只需要它作為字符串呈現，則以下代碼更容易

NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:@"HH:mm"];

NSString *startTimeString = [formatter stringFromDate:startTimePicker.date];

Answer 3

這似乎是我的問題所在，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

您可以在這里找到所需的一切：
https://developer.apple.com/library/content/documentation/Cocoa/Conceptual/DatesAndTimes/Articles/dtCalendars.html

Answer 5

如果您要使用C庫，那么可以這樣做：

time_t t;
struct tm * timeinfo;

time (&t);
timeinfo = localtime (&t);

NSLog(@"Hour: %d Minutes: %d", timeinfo->tm_hour, timeinfo->tm_min);

並使用Swift：

var t = time_t()
time(&t)
let x = localtime(&t)

println("Hour: \(x.memory.tm_hour) Minutes: \(x.memory.tm_min)")

如需進一步指導，請訪問： http ： //www.cplusplus.com/reference/ctime/localtime/

Answer 6

在iOS 8中，Apple引入了一種輔助方法來從NSDate對象中檢索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 7

Swift 2.0

從日期開始，你可以做以下事情來獲得時間和分鍾：

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

Answer 8

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))

請注意print語句中對String的強制轉換，您可以輕松地將該值賦給變量，如下所示：

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

然后你可以連接像這樣的值：

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

Answer 9

這是 NSDate 的擴展

    @interface NSDate (KTelDateUtility)

-(NSUInteger)dateYear;
-(NSUInteger)dateMonth;
-(NSUInteger)dateDay;

-(NSUInteger)dateHours;
-(NSUInteger)dateMins;
-(NSUInteger)dateSeconds;

@end

    @implementation NSDate (KTelDateUtility)

-(NSDateComponents*)dateCalenderComponents {
    NSDateComponents* dateComponents = [[NSCalendar currentCalendar] components:NSCalendarUnitDay | NSCalendarUnitMonth | NSCalendarUnitYear fromDate:self];
    return dateComponents;
}

-(NSDateComponents*)dateTimeComponents {
    NSDateComponents* timeComponents = [[NSCalendar currentCalendar] components:NSCalendarUnitHour | NSCalendarUnitMinute | NSCalendarUnitSecond fromDate:self];
    return timeComponents;
}

-(NSUInteger)dateYear {
    return [[self dateCalenderComponents] year];
}

-(NSUInteger)dateMonth {
    return [[self dateCalenderComponents] month];
}

-(NSUInteger)dateDay {
    return [[self dateCalenderComponents] day];
}

-(NSUInteger)dateHours {
    return [[self dateTimeComponents] hour];
}

-(NSUInteger)dateMins {
    return [[self dateTimeComponents] minute];
}

-(NSUInteger)dateSeconds {
    return [[self dateTimeComponents] second];
}


@end