xcode 如何在 iphone 中以 24 小时格式转换时间？
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How to convert time in 24 hr format in iphone?
提问by 07405
I have to convert the given time in 24 hr format.But I did not get it.Don't know where I m going wrong. If I have TimeStart as 1:15 PM then I should get 13:15 ..
我必须以 24 小时格式转换给定的时间。但我没有得到它。不知道我哪里出错了。如果我将 TimeStart 设为下午 1:15，那么我应该得到 13:15 ..
Item *item=[sectionItems objectAtIndex:itemId];
NSLog(@"%@",item.TimeStart);
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"HH:mm a"];
NSString *formattedDateString = [dateFormatter stringFromDate:item.TimeStart];
NSLog(@"%@",formattedDateString);
In the code above I have a Item class and that I have NSString*TimeStart;
When I see formattedDateString it is returning null.How can I fix it ?
在上面的代码中，我有一个 Item 类并且我有NSString*TimeStart; 当我看到 formattedDateString 时，它返回 null。我该如何解决？
回答by Paras Joshi
Item *item=[sectionItems objectAtIndex:itemId];
NSLog(@"%@",item.TimeStart);
NSString *str = @"1:45.PM";// put here item.TimeStart
NSDateFormatter *dateFormatter = [[[NSDateFormatter alloc] init] autorelease];
[dateFormatter setDateFormat:@"hh:mm.a"];// here give the format which you get in TimeStart
NSDate *date = [dateFormatter dateFromString: str];
dateFormatter = [[[NSDateFormatter alloc] init] autorelease];
[dateFormatter setDateFormat:@"HH:mm"];
NSString *convertedString = [dateFormatter stringFromDate:date];
NSLog(@"Converted String : %@",convertedString);
回答by Nitin Gohel
i just simply setDateFormat like [formatter setDateFormat:@"HH:mm"];Remove a
我只是简单地 setDateFormat 像[formatter setDateFormat:@"HH:mm"];Removea
and below caode for checking its time formate is 24 hr or 12
和下面的 caode 检查其时间格式是 24 小时或 12
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setLocale:[NSLocale currentLocale]];
[formatter setDateStyle:NSDateFormatterNoStyle];
[formatter setTimeStyle:NSDateFormatterShortStyle];
NSString *dateString = [formatter stringFromDate:[NSDate date]];
NSRange amRange = [dateString rangeOfString:[formatter AMSymbol]];
NSRange pmRange = [dateString rangeOfString:[formatter PMSymbol]];
BOOL is24h = (amRange.location == NSNotFound && pmRange.location == NSNotFound);
[formatter release];
NSLog(@"%@\n",(is24h ? @"YES" : @"NO"));
回答by iPhone Programmatically
Use this to set 24 hr format.
使用它来设置 24 小时格式。
[currentDate setDateFormat:@"yyyy-MM-dd HH:mm"];
or
或者
[formatter setDateFormat:@"HH:mm"];
without using formatter
不使用格式化程序
NSRange range;
range.location = 2;
range.length = 2;
NSString *dateString=[NSString stringWithFormat:@"%@:%@",[myString substringToIndex:2], [myString substringWithRange:range]];
This is the code i am using in my project and its working for me
这是我在我的项目中使用的代码，它对我有用
NSDateFormatter *dateFormatter = [[[NSDateFormatter alloc] init] autorelease];
[dateFormatter setDateFormat:@"HH:mm"];
NSString *dateString = [dateFormatter stringFromDate:[NSDate date]];
NSLog(@"Current time date:%@", dateString);
output:Current time date:14:41
输出：当前时间日期：14:41
