NSDateFormatter dateFromString conversion - objective-c

Question

I am having problems with conversion of NSString object to NSDate. Here is what I want to do:
I am downloading an RSS Message from the internet. I have the whole message parsed by NSXMLParser. After that, I have parts like , or saved to particular NSStrings. I want to convert element (that includes publication date of RSS Message) to NSDate so that I could perform some operations on it like on a date object (e.g. sorting, showing on a clock etc.). Here is the way my looks like:
"Wed, 25 Sep 2013 12:56:57 GMT"
I tried to convert it to NSDate in this way:
*//theString is NSString containing my date as a text
NSDate *dateNS = [[NSDate alloc] init];
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"EEE, dd MMM yyyy hh:mm:ss ZZZ"];
dateNS = [dateFormatter dateFromString:theString];*
However, after doing above code, dateNS always appear to be (null).
My question is simple: what is the right way to convert NSString with date formatted like this to NSDate object?
By the way, I have seen the website
http://www.unicode.org/reports/tr35/tr35-25.html#Date_Format_Patterns
It seems that there are many ways to format particular date, but I could not find what I am doing wrong.

Answer 1

Your problem is the your date formatter has not identical fort as your date string:
You should set date formatter the same format like your date string
My Example:
// Convert string to date
NSString *beginString = #"Sat, 30 Dec 2013 14:45:00 EEST";
//beginString = [beginString stringByReplacingOccurrencesOfString:#"EEST" withString:#""];
//beginString = [beginString stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
dateFormat = [[NSDateFormatter alloc] init];
[dateFormat setLocale:[[NSLocale alloc] initWithLocaleIdentifier:#"en_GB"]];
[dateFormat setTimeZone:[NSTimeZone timeZoneWithName:#"Europe/Helsinki"]];
[dateFormat setDateFormat:#"EEE, dd MMM yyyy HH:mm:ss z"];
dateFromString = [dateFormat dateFromString:beginString];
//NSLog(#"Begin string: %#", beginString);
//NSLog(#"not formated: %#", dateFromString);
// Convert Date to string
[dateFormat setTimeZone:[NSTimeZone localTimeZone]];
[dateFormat setLocale:[[NSLocale alloc] initWithLocaleIdentifier:#"ru_RU"]];
[dateFormat setDateFormat:#"dd MMMM yyyy"];
myStrDate = [dateFormat stringFromDate:dateFromString];
[currentTitle setPubDate:myStrDate];

Answer 2

NSDate * dateNS = [[NSDate alloc] init]; is useless, you don't need to allocate any date object.
NSDateFormatter * dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"EEE, dd MMM yyyy HH:mm:ss ZZZ"];
NSLog(#"%#", [dateFormatter dateFromString:#"Wed, 25 Sep 2013 12:56:57 GMT"]);
Outputs the date correctly, are you sure theString isn't nil?