iOS调用系统的发短信功能可以分为两种：1，程序外调用系统发短信。2，程序内调用系统发短信。第二种的好处是用户发短信之后还可以回到app。这对app来说非常重要。

程序外调用系统发短信

这个方法其实很简单，直接调用openURL即可：

[[UIApplication sharedApplication]openURL:[NSURL URLWithString:@"sms://13888888888"]];

程序内调用系统发短信

1）导入MessageUI.framework，并引入头文件：

#import <MessageUI/MessageUI.h>

2）实现代理方法MFMessageComposeViewControllerDelegate

  -(void)messageComposeViewController:(MFMessageComposeViewController *)controller didFinishWithResult:(MessageComposeResult)result
{
    [self dismissViewControllerAnimated:YES completion:nil];
    switch (result) {
        case MessageComposeResultSent:
            //信息传送成功

            break;
        case MessageComposeResultFailed:
            //信息传送失败

            break;
        case MessageComposeResultCancelled:
            //信息被用户取消传送

            break;
        default:
            break;
    }
}

3）发送短信

  -(void)showMessageView:(NSArray *)phones title:(NSString *)title body:(NSString *)body
{
    if( [MFMessageComposeViewController canSendText] )
    {
        MFMessageComposeViewController * controller = [[MFMessageComposeViewController alloc] init];
        controller.recipients = phones;
        controller.navigationBar.tintColor = [UIColor redColor];
        controller.body = body;
        controller.messageComposeDelegate = self;
        [self presentViewController:controller animated:YES completion:nil];
        [[[[controller viewControllers] lastObject] navigationItem] setTitle:title];//修改短信界面标题
    }
    else
    {
        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"提示信息"
                                                        message:@"该设备不支持短信功能"
                                                       delegate:nil
                                              cancelButtonTitle:@"确定"
                                              otherButtonTitles:nil, nil];
        [alert show];
    }
}

参数phones：发短信的手机号码的数组，数组中是一个即单发,多个即群发。

4）调用发短信的方法

    [self showMessageView:[NSArray arrayWithObjects:@"13888888888",@"13999999999", nil] title:@"test" body:@"你是土豪么，么么哒"];

我的微信iOS开发：iOSDevTip

代码下载地址:SendMsgMaster