Regular expression for date formats in iOS - ios

Question

In my project i need to check some format coming from server, So i want to write a regular expression to check the format.
This is the format "03/31/2013 08:00:00" and other format is "03/31/2003 08:00 AM/PM"
How can i check this date formats. Can any one help me.
Regards
Kiran

Answer 1

^(?:\d{2}\/){2}\d{4} \d{2}:\d{2}(?::\d{2}| (?:AM|PM))?$
Note that it won't check for incorrect values.

Answer 2

If you want to get NSDate from this string, you should use NSDateFormetter instead:
NSString * date = #"03/31/2013 08:00:00"; // source string
NSDateFormatter * date_formatter = [[NSDateFormatter alloc] init];
[date_formatter setDateFormat: #"MM/dd/yyyy HH:mm:ss"]; // your date format
NSDate * result = [date_formatter dateFromString: date]; // converting
NSLog (#"%#", [result description]); // log your date result
[date_format release];

Answer 3

Not a real answer to your question about regex but, if you want to get the date from the dateString received from server you can try a trial and error method with the dateFormat of NSDateFormatter.
NSString *dateFormat1 = #"MM/dd/yyyy HH:mm:ss";
NSString *dateFormat2 = #"MM/dd/yyyy hh:mm:ss a";
NSString *dateString = #"03/31/2013 08:00:00 AM";
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc]init];
NSLocale *enUSPOSIXLocale = [[NSLocale alloc] initWithLocaleIdentifier:#"en_US_POSIX"];
[dateFormatter setLocale:enUSPOSIXLocale];
[dateFormatter setDateFormat:dateFormat1];
NSDate *date = [dateFormatter dateFromString:dateString];
if (!date) {
[dateFormatter setDateFormat:dateFormat2];
date = [dateFormatter dateFromString:dateString];
}
NSLog(#"Date : %#",date);