遵循以下步骤

1 .添加消息i。项目框架

2。在.h文件中导入# Import <MessageUI/MessageUI.h>。

3.复制此代码以发送消息

 if ([MFMessageComposeViewController canSendText]) {
    MFMessageComposeViewController *messageComposer =
    [[MFMessageComposeViewController alloc] init];
    NSString *message = @"Message!!!";
    [messageComposer setBody:message];
    messageComposer.messageComposeDelegate = self;
    [self presentViewController:messageComposer animated:YES completion:nil];
}

4所示。实现委托方法，如果你想。

- (void)messageComposeViewController:(MFMessageComposeViewController *)controller didFinishWithResult:(MessageComposeResult)result{


   ///your stuff here 

    [self dismissViewControllerAnimated:YES completion:nil];
}

快跑!

如果你想在你自己的应用程序中显示创建和发送消息，你需要使用MFMessageComposeViewController。

否则，您可以使用sharedApplication方法。

这是一个教程，它完全是你正在寻找的:MFMessageComposeViewController。

http://blog.mugunthkumar.com/coding/iphone-tutorial-how-to-send-in-app-sms/

从本质上讲:

MFMessageComposeViewController *controller = [[[MFMessageComposeViewController alloc] init] autorelease];
if([MFMessageComposeViewController canSendText])
{
    controller.body = @"SMS message here";
    controller.recipients = [NSArray arrayWithObjects:@"1(234)567-8910", nil];
    controller.messageComposeDelegate = self;
    [self presentModalViewController:controller animated:YES];
}

还有文档的链接。

https://developer.apple.com/documentation/messageui/mfmessagecomposeviewcontroller

//使用名称和数字调用方法。

-(void)openMessageViewWithName:(NSString*)contactName withPhone:(NSString *)phone{

CTTelephonyNetworkInfo *networkInfo=[[CTTelephonyNetworkInfo alloc]init];

CTCarrier *carrier=networkInfo.subscriberCellularProvider;

NSString *Countrycode = carrier.isoCountryCode;

if ([Countrycode length]>0)     //Check If Sim Inserted
{

    [self sendSMS:msg recipientList:[NSMutableArray arrayWithObject:phone]];
}
else
{

    [AlertHelper showAlert:@"Message" withMessage:@"No sim card inserted"];
}

}

//发送消息的方法

- (void)sendSMS:(NSString *)bodyOfMessage recipientList:(NSMutableArray *)recipients{  
 MFMessageComposeViewController *controller1 = [[MFMessageComposeViewController alloc] init] ;
 controller1 = [[MFMessageComposeViewController alloc] init] ;
 if([MFMessageComposeViewController canSendText])
{
    controller1.body = bodyOfMessage;
    controller1.recipients = recipients;
    controller1.messageComposeDelegate = self;
    [self presentViewController:controller1 animated:YES completion:Nil];
 }
}

您可以使用sms:[目标电话号码]URL打开sms应用程序，但没有指示如何用文本预填充sms正文。

添加MessageUI。框架并使用下面的代码

#import <MessageUI/MessageUI.h> 

然后:

if ([MFMessageComposeViewController canSendText]) {
  MFMessageComposeViewController *messageComposer =
  [[MFMessageComposeViewController alloc] init];
  NSString *message = @"Your Message here";
  [messageComposer setBody:message];
  messageComposer.messageComposeDelegate = self;
  [self presentViewController:messageComposer animated:YES completion:nil];
}

以及委托方法-

- (void)messageComposeViewController:(MFMessageComposeViewController *)controller
             didFinishWithResult:(MessageComposeResult)result {
      [self dismissViewControllerAnimated:YES completion:nil];
 }