//  调用系统API发送短信        - (void)didClickSendMessageButtonAction{                        if ([MFMessageComposeViewController canSendText] == YES) {                                MFMessageComposeViewController *messageVC = [[MFMessageComposeViewController alloc] init];                //  设置代理<MFMessageComposeViewControllerDelegate>                messageVC.messageComposeDelegate = self;                //  发送To Who                messageVC.recipients = @[@"18757289870"];                messageVC.body = @"hello world";                [self presentViewController:messageVC animated:YES completion:nil];                            }else{                            NSLog(@"此设备不支持");            }        }                - (void)messageComposeViewController:(MFMessageComposeViewController *)controller didFinishWithResult:(MessageComposeResult)result{                        switch (result) {                case MessageComposeResultCancelled:                    NSLog(@"取消发送");                    break;                case MessageComposeResultFailed:                    NSLog(@"发送失败");                    break;                case MessageComposeResultSent:                    NSLog(@"发送成功");                    break;                default:                    break;            }                        [self dismissViewControllerAnimated:YES completion:nil];                }                //  调用系统应用程序发送消息        - (void)didClickSendMessage2ButtonAction{                        NSURL *url = [NSURL URLWithString:@"sms:18656348970"];            if ([[UIApplication sharedApplication] canOpenURL:url] == YES) {                                [[UIApplication sharedApplication] openURL:url];                            }else{                            NSLog(@"失败");            }                }