NSURL encoding using iso-8859-1 instead of UTF8

I need to convert a NSString to a NSURL using the iso-8859-1 instead of UTF8 (like here: Re-encode url from utf-8 encoded to iso-88开发者_StackOverflow社区59-1 encoded) but i don't know how to achieve it.

For example:

http://www.example.com/català 

should be

http://www.example.com/catal%E1

insted of

http://www.example.com/catal%C3%A0

Thanks in advice!

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You probably want the NSString method stringByAddingPercentEscapesUsingEncoding: