ios - 如何从 NSDate 获取小时和分钟？

Question

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11:59:13 AM来自日期选择器的内容。

在这里，如果我使用上面的代码，如果它大于 9，则可以获取小时。否则我需要更改NSMakeRange(0,1)以获取 1 到 9 之间的小时。

有什么方法可以获取小时、分钟等？

在此先感谢，请提供我的示例代码。

score 265 · Accepted Answer

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

对象-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

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

有关日期格式的更多信息，请参见官方 unicode 网站

score 53 · Accepted Answer

如果您只需要将其呈现为字符串，则以下代码会容易得多

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

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

score 45 · Accepted Answer

在我看来，这就是问题所在，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];

score 6 · Accepted Answer

NSDateComponents

您需要的一切都可以在这里找到：
https ://developer.apple.com/library/content/documentation/Cocoa/Conceptual/DatesAndTimes/Articles/dtCalendars.html

score 4 · Accepted Answer

如果您要使用 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);

并使用斯威夫特：

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

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

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

score 4 · Accepted Answer

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

Objective-C

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)")
}

score 3 · Accepted Answer

斯威夫特 2.0

您可以执行以下操作来获取日期的小时和分钟：

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

score 2 · Accepted Answer

斯威夫特 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 print 语句中对 String 的强制转换，您可以轻松地将该值分配给变量，如下所示：

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

然后你可以像这样连接值：

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

ios - 如何从 NSDate 获取小时和分钟？

8 回答 8

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