NSDateFormatter dateFromString coming back null - objective-c

Question

I am trying to get a string date into a date object so I can do some comparisons. My code is as follows:
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:#"yyyy/MM/dd_hh:mm:ss"];
NSDate *date = [formatter dateFromString:#"2012/02/06_20:35:59"];
[formatter release];
NSLog(#"date = %#", date);
My NSLog is showing that *date = null;
Any help is appreciated. Thanks.

Answer 1

Does't your format need to be yyyy/MM/dd_HH:mm:ss?
hh is 0-12 where as HH is 0-23.
For reference, here is the doc where I got that nugget of information from - http://unicode.org/reports/tr35/tr35-10.html#Date_Format_Patterns

Answer 2

NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:#"yyyy-MM-dd HH:mm:ss"];
NSDate *date = [formatter dateFromString:#"2012-02-06 20:35:59"];
[formatter release];
NSLog(#"date = %#", date);
d Day of the month as digits; no leading zero for single-digit days.
dd Day of the month as digits; leading zero for single-digit days.
ddd Day of the week as a three-letter abbreviation.
dddd Day of the week as its full name.
m Month as digits; no leading zero for single-digit months.
mm Month as digits; leading zero for single-digit months.
mmm Month as a three-letter abbreviation.
mmmm Month as its full name.
yy Year as last two digits; leading zero for years less than 10.
yyyy Year represented by four digits.
h Hours; no leading zero for single-digit hours (12-hour clock).
hh Hours; leading zero for single-digit hours (12-hour clock).
H Hours; no leading zero for single-digit hours (24-hour clock).
HH Hours; leading zero for single-digit hours (24-hour clock).
M Minutes; no leading zero for single-digit minutes.
Uppercase M unlike CF timeFormat‘s m to avoid conflict with months.
MM Minutes; leading zero for single-digit minutes.
Uppercase MM unlike CF timeFormat‘s mm to avoid conflict with months.
s Seconds; no leading zero for single-digit seconds.
ss Seconds; leading zero for single-digit seconds.