Question

I would like to write a string to an NSURL which may contain characters such as / or :, which are not supported by the file system. Is there any convenience method to trim these characters? Or maybe a reference containing all illegal characters, so that I can write such a method myself?

Answer 1

May be it’s better just to escape them with something like this:

NSString *unescaped = @"http://www";
NSString *escapedString = (NSString *)CFURLCreateStringByAddingPercentEscapes(
    NULL,
   (CFStringRef)unescaped,
    NULL,
   (CFStringRef)@"!*'();:@&=+$,/?%#[]",
    kCFStringEncodingUTF8);

NSLog(@"escapedString: %@",escapedString);

as it stated here?

Or you can just strip ! * ‘ ( ) ; : @ & = + $ , / ? % # [ ] characters, if you wish so.
Look here for a list of reserved characters.