Here is the sample I can up with: -(IBAction)getToken:(id)sender { NSString *clientSecret = (__bridge NSString *)CFURLCreateStringByAddingPercentEscapes(NULL, (CFStringRef)CLIENT_SECRETCODE, NULL, (CFStringRef) @"!*'();:@&=+$,/?%#[]", kCFStringEncodingUTF8); NSMutableString* authHeader = [NSMutableString stringWithString:@"client_id="]; [authHeader appendString:CLIENT_ID]; [authHeader appendString
