Iphone: NSString to NSDate

Hi Im开发者_如何学Go trying to convert an NSString to NSDate

NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss ZZZZ"];
NSDate *dateFromString = [[NSDate alloc] init];
dateFromString = [dateFormatter dateFromString:lastModified];

But when I do a

NSLog(@" date: %@ ", dateFromString);

I get date: (null)

The lastModified string has date in string format as "Tue, 15 Feb 2011 13:30:42 GMT"

What am I doing wrong?

your input (lastModified) does not match the specified date format.

a properly formed string representation of the time specified by lastModified for the date format is:

"2011-02-15 13:30:42 GMT", but you're passing "Tue, 15 Feb 2011 13:30:42 GMT".