NSString *string = [self jsonObjectToJSONString:inputDataDic];

 -(NSString*)jsonObjectToJSONString:(id)object

 {

     if ([NSJSONSerialization isValidJSONObject:object]) {

         NSString *jsonString = nil;

         NSError *error;

         NSData *jsonData = [NSJSONSerialization dataWithJSONObject:object

                                                            options:NSJSONWritingPrettyPrinted // Pass 0 if you don't care about the readability of the generated string

                                                              error:&error];

         if (!jsonData) {

             NSLog(@"Got an error: %@", error);

         } else {

             jsonString = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];

         }

         return jsonString;

     }else{

         return nil;

     }

 }