hi, I'm trying to check if a given URL is valid and i'm doing it like this:

- (BOOL)urlIsValid:(NSString *)address {
    NSURL *testURL = [NSURL URLWithString:address];
    if (testURL == nil) {
        return NO;
    }
    else {
        return YES;
    }
}

Since "URLWithString" is supposed to return "nil" if the URL is malformed I thought this would work but it doesn't for some reason. Could someone please tell me why? Thanks in advance!