- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{    // 1.URL    NSURL *url = [NSURL URLWithString:@"http://localhost:8080/MJServer/order"];        // 2.请求    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];        // 3.请求方法    request.HTTPMethod = @"POST";        // 4.设置请求体（请求参数）    // 创建一个描述订单信息的JSON数据    NSDictionary *orderInfo = @{                                @"shop_id" : @"1243324",                                @"shop_name" : @"啊哈哈哈",                                @"user_id" : @"899"                                };    NSData *json = [NSJSONSerialization dataWithJSONObject:orderInfo options:NSJSONWritingPrettyPrinted error:nil];    request.HTTPBody = json;        // 5.设置请求头：这次请求体的数据不再是普通的参数，而是一个JSON数据    [request setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];        // 6.发送请求    [NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {        if (data == nil || connectionError) return;        NSDictionary *dict = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableLeaves error:nil];        NSString *error = dict[@"error"];        if (error) {            [MBProgressHUD showError:error];        } else {            NSString *success = dict[@"success"];            [MBProgressHUD showSuccess:success];        }    }];    }