it may be very easy, but I don't seems to find out why is URLWithString: returning nil here.

//localisationName is a arbitrary string here
NSString* webName = [localisationName stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]; 
NSString* stringURL = [NSString stringWithFormat:@"http://maps.google.com/maps/geo?q=%@,Montréal,Communauté-Urbaine-de-Montréal,Québec,Canadae&output=csv&oe=utf8&sensor=false&key=", webName];
NSURL* url = [NSURL URLWithString:stringURL];

Solution 1:

You need to escape the non-ASCII characters in your hardcoded URL as well:

//localisationName is a arbitrary string here
NSString* webName = [localisationName stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]; 
NSString* stringURL = [NSString stringWithFormat:@"http://maps.google.com/maps/geo?q=%@,Montréal,Communauté-Urbaine-de-Montréal,Québec,Canadae&output=csv&oe=utf8&sensor=false", webName];
NSString* webStringURL = [stringURL stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSURL* url = [NSURL URLWithString:webStringURL];

You can probably remove the escaping of the localisationName since it will be handled by the escaping of the whole string.

Solution 2:

Use This Function if you deal with file saved on file manager.

NSURL *_url = [NSURL fileURLWithPath:path];

Solution 3:

I guess you need to use -[NSString stringByAddingPercentEscapesUsingEncoding:]. See Apple doc.

Another comment is that, as an old timer, I find it a bit uneasy to put non-ASCII characters in a source file. That said, this Apple doc says, starting from 10.4, UTF-16 strings are OK inside @"...". Somehow GCC seems to correctly convert the source file in Latin-1 into UTF-16 in the binary, but I think it's safest to use 7-bit ASCII characters only inside the source code, and use NSLocalizedString.