IOS系统框架提供的两种发送Email的方法：openURL 和 MFMailComposeViewController。借助这两个方法，我们可以轻松的在应用里加入如用户反馈这类需要发送邮件的功能。
1.openURL
使用openURL调用系统邮箱客户端是我们在IOS3.0以下实现发邮件功能的主要手段。我们可以通过设置url里的相关参数来指定邮件的内容，不过其缺点很明显，这样的过程会导致程序暂时退出。下面是使用openURL来发邮件的一个小例子：
#pragma mark - 使用系统邮件客户端发送邮件
-(void)launchMailApp
{
NSMutableString *mailUrl = [[[NSMutableString alloc]init]autorelease];
//添加收件人
NSArray *toRecipients = [NSArray arrayWithObject: @"[email protected]"];
[mailUrl appendFormat:@"mailto:%@", [toRecipients componentsJoinedByString:@","]];
//添加抄送
NSArray *ccRecipients = [NSArray arrayWithObjects:@"[email protected]", @"[email protected]", nil];
[mailUrl appendFormat:@"?cc=%@", [ccRecipients componentsJoinedByString:@","]];
//添加密送
NSArray *bccRecipients = [NSArray arrayWithObjects:@"[email protected]", nil];
[mailUrl appendFormat:@"&bcc=%@", [bccRecipients componentsJoinedByString:@","]];
//添加主题
[mailUrl appendString:@"&subject=my email"];
//添加邮件内容
[mailUrl appendString:@"&body=<b>email</b> body!"];
NSString* email = [mailUrl stringByAddingPercentEscapesUsingEncoding: NSUTF8StringEncoding];
[[UIApplication sharedApplication] openURL: [NSURL URLWithString:email]];
}
缺点很明显，这样的过程会导致程序暂时退出，即使在iOS 4.x支持多任务的情况下，这样的过程还是会让人觉得不是很方便。
2.MFMailComposeViewController
MFMailComposeViewController是在IOS3.0新增的一个接口，它在MessageUI.framework中。通过调用MFMailComposeViewController，可以把邮件发送窗口集成到我们的应用里，发送邮件就不需要退出程序了。MFMailComposeViewController的使用方法：
- 1.项目中引入MessageUI.framework；
- 2.在使用的文件中导入MFMailComposeViewController.h头文件；
- 3.实现MFMailComposeViewControllerDelegate，处理邮件发送事件；
- 4.调出邮件发送窗口前先使用MFMailComposeViewController里的“+ (BOOL)canSendMail”方法检查用户是否设置了邮件账户；
- 5.初始化MFMailComposeViewController，构造邮件体
// // ViewController.h // MailDemo // // Created by LUOYL on 12-4-4. // Copyright (c) 2012年 http://luoyl.info. All rights reserved. // #import <UIKit/UIKit.h> #import <MessageUI/MFMailComposeViewController.h> @interface ViewController : UIViewController<MFMailComposeViewControllerDelegate> @end
#pragma mark - 在应用内发送邮件
//激活邮件功能
- (void)sendMailInApp
{
Class mailClass = (NSClassFromString(@"MFMailComposeViewController"));
if (!mailClass) {
[self alertWithMessage:@"当前系统版本不支持应用内发送邮件功能，您可以使用mailto方法代替"];
return;
}
if (![mailClass canSendMail]) {
[self alertWithMessage:@"用户没有设置邮件账户"];
return;
}
[self displayMailPicker];
}
//调出邮件发送窗口
- (void)displayMailPicker
{
MFMailComposeViewController *mailPicker = [[MFMailComposeViewController alloc] init];
mailPicker.mailComposeDelegate = self;
//设置主题
[mailPicker setSubject: @"eMail主题"];
//添加收件人
NSArray *toRecipients = [NSArray arrayWithObject: @"[email protected]"];
[mailPicker setToRecipients: toRecipients];
//添加抄送
NSArray *ccRecipients = [NSArray arrayWithObjects:@"[email protected]", @"[email protected]", nil];
[mailPicker setCcRecipients:ccRecipients];
//添加密送
NSArray *bccRecipients = [NSArray arrayWithObjects:@"[email protected]", nil];
[mailPicker setBccRecipients:bccRecipients];
// 添加一张图片
UIImage *addPic = [UIImage imageNamed: @"[email protected]"];
NSData *imageData = UIImagePNGRepresentation(addPic); // png
//关于mimeType：http://www.iana.org/assignments/media-types/index.html
[mailPicker addAttachmentData: imageData mimeType: @"" fileName: @"Icon.png"];
//添加一个pdf附件
NSString *file = [self fullBundlePathFromRelativePath:@"高质量C++编程指南.pdf"];
NSData *pdf = [NSData dataWithContentsOfFile:file];
[mailPicker addAttachmentData: pdf mimeType: @"" fileName: @"高质量C++编程指南.pdf"];
NSString *emailBody = @"<font color='red'>eMail</font> 正文";
[mailPicker setMessageBody:emailBody isHTML:YES];
[self presentModalViewController: mailPicker animated:YES];
[mailPicker release];
}
#pragma mark - 实现 MFMailComposeViewControllerDelegate
- (void)mailComposeController:(MFMailComposeViewController *)controller didFinishWithResult:(MFMailComposeResult)result error:(NSError *)error
{
//关闭邮件发送窗口
[self dismissModalViewControllerAnimated:YES];
NSString *msg;
switch (result) {
case MFMailComposeResultCancelled:
msg = @"用户取消编辑邮件";
break;
case MFMailComposeResultSaved:
msg = @"用户成功保存邮件";
break;
case MFMailComposeResultSent:
msg = @"用户点击发送，将邮件放到队列中，还没发送";
break;
case MFMailComposeResultFailed:
msg = @"用户试图保存或者发送邮件失败";
break;
default:
msg = @"";
break;
}
[self alertWithMessage:msg];
}
第二种方法的劣势也很明显，iOS系统替我们提供了一个mail中的UI，而我们却完全无法对齐进行订制，这会让那些定制化成自己风格的App望而却步，因为这样使用的话无疑太突兀了。
3、我们可以根据自己的UI设计需求来定制相应的视图以适应整体的设计。可以使用比较有名的开源SMTP协议来实现。
https://github.com/jetseven/skpsmtpmessage
在SKPSMTPMessage类中，并没有对视图进行任何的要求，它提供的都是数据层级的处理，你之需要定义好相应的发送要求就可以实现邮件发送了。至于是以什么样的方式获取这些信息，就可以根据软件的需求来确定交互方式和视图样式了。
SKPSMTPMessage *testMsg = [[SKPSMTPMessage alloc] init]; testMsg.fromEmail = @"[email protected]"; testMsg.toEmail =@"[email protected]"; testMsg.relayHost = @"smtp.gmail.com"; testMsg.requiresAuth = YES; testMsg.login = @"[email protected]"; testMsg.pass = @"test"; testMsg.subject = [NSString stringWithCString:"测试" encoding:NSUTF8StringEncoding]; testMsg.bccEmail = @"[email protected]"; testMsg.wantsSecure = YES; // smtp.gmail.com doesn't work without TLS! // Only do this for self-signed certs! // testMsg.validateSSLChain = NO; testMsg.delegate = self; NSDictionary *plainPart = [NSDictionary dictionaryWithObjectsAndKeys:@"text/plain",kSKPSMTPPartContentTypeKey, [NSString stringWithCString:"测试正文" encoding:NSUTF8StringEncoding], kSKPSMTPPartMessageKey,@"8bit",kSKPSMTPPartContentTransferEncodingKey,nil]; NSString *vcfPath = [[NSBundle mainBundle] pathForResource:@"test" ofType:@"vcf"]; NSData *vcfData = [NSData dataWithContentsOfFile:vcfPath]; NSDictionary *vcfPart = [NSDictionary dictionaryWithObjectsAndKeys: @"text/directory;\r\n\tx-unix-mode=0644;\r\n\tname=\"test.vcf\"",kSKPSMTPPartContentTypeKey, @"attachment;\r\n\tfilename=\"test.vcf\"",kSKPSMTPPartContentDispositionKey, [vcfData encodeBase64ForData],kSKPSMTPPartMessageKey,@"base64",kSKPSMTPPartContentTransferEncodingKey,nil]; testMsg.parts = [NSArray arrayWithObjects:plainPart,vcfPart,nil]; [testMsg send];
该类也提供了相应的Delegate方法来让你更好的获知发送的状态.
-(void)messageSent:(SKPSMTPMessage *)message; -(void)messageFailed:(SKPSMTPMessage *)message error:(NSError *)error;