我在较早时期的一篇文章《基于Lumisoft.NET实现的邮件发送功能》有大致对这个Lumisoft.NET组件的使用进行了介绍，在《DevExpress控件使用之RichEditControl的使用》则对使用.NET API进行邮件发送进行了说明，其实，实现邮件发送，这两种方式是比较常见的，当然Lumisoft.NET组件除了提供邮件发送功能外，还提供了邮件接收等功能的处理（包括基于POP3协议和IMAP协议），而.NET则除了提供SMTP协议功能外，则没有提供POP3协议处理的相关类库，因此收取邮件这需要自己进行封装（需要也可以参考codeproject.com上的相关文章）。
1、.NET的邮件发送功能实现
.NET本身封装了一个SmtpClient类以及相关的邮件对象类，这样利用这些类库，也可以方便实现邮件的发送功能的了。
如添加发送人地址，抄送地址，以及暗送地址（多个地址用逗号分开）代码如下。
string toEmails = mailInfo.ToEmail; string bcc = ""; mailInfo.RecipientBCC.ForEach(obj => bcc += string.Format("{0},", obj)); bcc = bcc.Trim(','); string cc = ""; mailInfo.RecipientCC.ForEach(obj => cc += string.Format("{0},", obj)); cc = cc.Trim(','); MailMessage mail = new MailMessage(settingInfo.MailFrom, toEmails); if (!string.IsNullOrEmpty(bcc)) { mail.Bcc.Add(bcc); } if (!string.IsNullOrEmpty(cc)) { mail.CC.Add(cc); }
.NET的附件和嵌入式资源由对象Attachment和LinkedResource进行管理，他们的利用代码如下所示：
//附件 foreach (string fileName in mailInfo.Attachments) { mail.Attachments.Add(new Attachment(fileName)); } //嵌入资源 AlternateView view = AlternateView.CreateAlternateViewFromString(mailInfo.Body, Encoding.UTF8, MediaTypeNames.Text.Html); foreach (LinkedAttachementInfo link in mailInfo.EmbedObjects) { LinkedResource resource = new LinkedResource(link.Stream, link.MimeType); resource.ContentId = link.ContentId; view.LinkedResources.Add(resource); } mail.AlternateViews.Add(view);
发送邮件的其他部分代码如下所示
mail.IsBodyHtml = mailInfo.IsBodyHtml; mail.BodyEncoding = Encoding.UTF8; mail.Subject = mailInfo.Subject; mail.SubjectEncoding = Encoding.UTF8; //发送账户设置信息 SmtpClient client = new SmtpClient(); client.Host = settingInfo.SmtpServer; client.Port = settingInfo.SmptPort; client.UseDefaultCredentials = false; client.DeliveryMethod = SmtpDeliveryMethod.Network; client.Credentials = new NetworkCredential(settingInfo.SmtpUser, settingInfo.SmtpPass); bool success = false; try { client.Send(mail); success = true; } catch (Exception ex) { LogTextHelper.Error(ex); //throw; }
上面利用.net的SmtpClient发送邮件操作的完整代码如下:
/// <summary> /// 发送外部邮件（系统配置，系统邮件） /// </summary> /// <param name="mailInfo">发送邮件信息</param> /// <returns></returns> public CommonResult Send(MailInfo mailInfo) { CommonResult result = new CommonResult(); try { AppConfig config = new AppConfig(); string MailDomain = config.AppConfigGet("MailDomain"); string MailUsername = config.AppConfigGet("MailUsername"); string MailPassword = config.AppConfigGet("MailPassword"); string MailPort = config.AppConfigGet("MailPort"); string MailFrom = config.AppConfigGet("MailFrom"); int port = 25; int.TryParse(MailPort, out port); SmtpSettingInfo settingInfo = new SmtpSettingInfo(MailDomain, port, MailUsername, MailPassword, MailFrom); result.Success = PrivateSendEmail(mailInfo, settingInfo); } catch (Exception ex) { result.ErrorMessage = ex.Message; throw; } return result; } /// <summary> /// 通用发送邮件操作 /// </summary> private static bool PrivateSendEmail(MailInfo mailInfo, SmtpSettingInfo settingInfo) { string toEmails = mailInfo.ToEmail; string bcc = ""; mailInfo.RecipientBCC.ForEach(obj => bcc += string.Format("{0},", obj)); bcc = bcc.Trim(','); string cc = ""; mailInfo.RecipientCC.ForEach(obj => cc += string.Format("{0},", obj)); cc = cc.Trim(','); MailMessage mail = new MailMessage(settingInfo.MailFrom, toEmails); if (!string.IsNullOrEmpty(bcc)) { mail.Bcc.Add(bcc); } if (!string.IsNullOrEmpty(cc)) { mail.CC.Add(cc); } //附件 foreach (string fileName in mailInfo.Attachments) { mail.Attachments.Add(new Attachment(fileName)); } //嵌入资源 AlternateView view = AlternateView.CreateAlternateViewFromString(mailInfo.Body, Encoding.UTF8, MediaTypeNames.Text.Html); foreach (LinkedAttachementInfo link in mailInfo.EmbedObjects) { LinkedResource resource = new LinkedResource(link.Stream, link.MimeType); resource.ContentId = link.ContentId; view.LinkedResources.Add(resource); } mail.AlternateViews.Add(view); mail.IsBodyHtml = mailInfo.IsBodyHtml; mail.BodyEncoding = Encoding.UTF8; mail.Subject = mailInfo.Subject; mail.SubjectEncoding = Encoding.UTF8; //发送账户设置信息 SmtpClient client = new SmtpClient(); client.Host = settingInfo.SmtpServer; client.Port = settingInfo.SmptPort; client.UseDefaultCredentials = false; client.DeliveryMethod = SmtpDeliveryMethod.Network; client.Credentials = new NetworkCredential(settingInfo.SmtpUser, settingInfo.SmtpPass); bool success = false; try { client.Send(mail); success = true; } catch (Exception ex) { LogTextHelper.Error(ex); //throw; } string message = string.Format("发送给【{0}】的邮件“{1}”，{2}，时间：{3}", mailInfo.ToEmail[0], mailInfo.Subject, success ? "发送成功" : "发送失败", DateTime.Now); LogTextHelper.Info(message); return success; }
2、基于Lumisoft.NET组件的邮件发送功能实现
基于Lumisoft.NET组件的邮件发送，也是一种很常用的，因为这个开源组件非常强大，经常可以在一些程序中被使用。
这个发送邮件的功能主要是利用SMTP_Client类来实现的，如下代码所示。注意其中的Authenticate函数已经被舍弃，可以使用Auth方法进行验证。但是函数参数有所不同，根据验证对象，使用不同的验证方式，一般选择AUTH_SASL_Client_Plain对象即可。
public bool Send() { bool sended = false; using (SMTP_Client client = new SMTP_Client()) { client.Connect(smtpServer, smtpPort, smtpUseSsl); client.EhloHelo(smtpServer); var authhh = new AUTH_SASL_Client_Plain(username, password); client.Auth(authhh); //client.Authenticate(username, password); //string text = client.GreetingText; client.MailFrom(from, -1); foreach (string address in toList.Keys) { client.RcptTo(address); } //采用Mail_Message类型的Stream Mail_Message m = Create_PlainText_Html_Attachment_Image(toList, ccList, from, fromDisplay, subject, body, attachments); using (MemoryStream stream = new MemoryStream()) { m.ToStream(stream, new MIME_Encoding_EncodedWord(MIME_EncodedWordEncoding.Q, Encoding.UTF8), Encoding.UTF8); stream.Position = 0; client.SendMessage(stream); sended = true; } if (m != null) { m.Dispose(); } client.Disconnect(); } return sended; }
构造用于SMTP发送的数据，可以使用Mail_Message 对象，也可以使用Mime对象，虽然读都可以实现发送功能，不过Mime对象是舍弃的对象了。
构造Mail_Message对象后，创建用于发送的格式要转换为Stream对象。转换为发送的Stream操作如下所示。
using (MemoryStream stream = new MemoryStream()) { m.ToStream(stream, new MIME_Encoding_EncodedWord(MIME_EncodedWordEncoding.Q, Encoding.UTF8), Encoding.UTF8); stream.Position = 0; client.SendMessage(stream); sended = true; }
构造Mail_Message格式的邮件操作如下所示。
private Mail_Message Create_PlainText_Html_Attachment_Image(Dictionary<string,string> tomails, Dictionary<string, string> ccmails, string mailFrom, string mailFromDisplay, string subject, string body, Dictionary<string, string> attachments, string notifyEmail = "", string plaintTextTips = "") { Mail_Message msg = new Mail_Message(); msg.MimeVersion = "1.0"; msg.MessageID = MIME_Utils.CreateMessageID(); msg.Date = DateTime.Now; msg.Subject = subject; msg.From = new Mail_t_MailboxList(); msg.From.Add(new Mail_t_Mailbox(mailFromDisplay, mailFrom)); msg.To = new Mail_t_AddressList(); foreach (string address in tomails.Keys) { string displayName = tomails[address]; msg.To.Add(new Mail_t_Mailbox(displayName, address)); } msg.Cc = new Mail_t_AddressList(); foreach (string address in ccmails.Keys) { string displayName = ccmails[address]; msg.Cc.Add(new Mail_t_Mailbox(displayName, address)); } //设置回执通知 if (!string.IsNullOrEmpty(notifyEmail) && ValidateUtil.IsEmail(notifyEmail)) { msg.DispositionNotificationTo.Add(new Mail_t_Mailbox(notifyEmail, notifyEmail)); } #region MyRegion //--- multipart/mixed ----------------------------------- MIME_h_ContentType contentType_multipartMixed = new MIME_h_ContentType(MIME_MediaTypes.Multipart.mixed); contentType_multipartMixed.Param_Boundary = Guid.NewGuid().ToString().Replace('-', '.'); MIME_b_MultipartMixed multipartMixed = new MIME_b_MultipartMixed(contentType_multipartMixed); msg.Body = multipartMixed; //--- multipart/alternative ----------------------------- MIME_Entity entity_multipartAlternative = new MIME_Entity(); MIME_h_ContentType contentType_multipartAlternative = new MIME_h_ContentType(MIME_MediaTypes.Multipart.alternative); contentType_multipartAlternative.Param_Boundary = Guid.NewGuid().ToString().Replace('-', '.'); MIME_b_MultipartAlternative multipartAlternative = new MIME_b_MultipartAlternative(contentType_multipartAlternative); entity_multipartAlternative.Body = multipartAlternative; multipartMixed.BodyParts.Add(entity_multipartAlternative); //--- text/plain ---------------------------------------- MIME_Entity entity_text_plain = new MIME_Entity(); MIME_b_Text text_plain = new MIME_b_Text(MIME_MediaTypes.Text.plain); entity_text_plain.Body = text_plain; //普通文本邮件内容，如果对方的收件客户端不支持HTML，这是必需的 string plainTextBody = "如果你邮件客户端不支持HTML格式，或者你切换到“普通文本”视图，将看到此内容"; if (!string.IsNullOrEmpty(plaintTextTips)) { plainTextBody = plaintTextTips; } text_plain.SetText(MIME_TransferEncodings.QuotedPrintable, Encoding.UTF8, plainTextBody); multipartAlternative.BodyParts.Add(entity_text_plain); //--- text/html ----------------------------------------- string htmlText = body;//"<html>这是一份测试邮件，<img src=\"cid:test.jpg\">来自<font color=red><b>LumiSoft.Net</b></font></html>"; MIME_Entity entity_text_html = new MIME_Entity(); MIME_b_Text text_html = new MIME_b_Text(MIME_MediaTypes.Text.html); entity_text_html.Body = text_html; text_html.SetText(MIME_TransferEncodings.QuotedPrintable, Encoding.UTF8, htmlText); multipartAlternative.BodyParts.Add(entity_text_html); //--- application/octet-stream ------------------------- WebClient client = new WebClient(); foreach (string attach in attachments.Keys) { try { byte[] bytes = client.DownloadData(attach); using (MemoryStream stream = new MemoryStream(bytes)) { multipartMixed.BodyParts.Add(Mail_Message.CreateAttachment(stream, attachments[attach])); } } catch (Exception ex) { LogTextHelper.Error(ex); } } #endregion return msg; }
而构造Mime格式的操作如下所示。
private Mime Create_Html_Attachment_Image(string mailTo, string mailFrom, string mailFromDisplay, string subject, string body, List<string> attachments, Dictionary<string, string> embedImages, string notifyEmail = "", string plaintTextTips = "", string replyEmail = "") { Mime m = new Mime(); MimeEntity mainEntity = m.MainEntity; mainEntity.From = new AddressList(); mainEntity.From.Add(new MailboxAddress(mailFromDisplay, mailFrom)); mainEntity.To = new AddressList(); mainEntity.To.Add(new MailboxAddress(mailTo, mailTo)); mainEntity.Subject = subject; mainEntity.ContentType = MediaType_enum.Multipart_mixed; //设置回执通知 if (!string.IsNullOrEmpty(notifyEmail) && ValidateUtil.IsEmail(notifyEmail)) { mainEntity.DSN = notifyEmail; } //设置统一回复地址 if (!string.IsNullOrEmpty(replyEmail) && ValidateUtil.IsEmail(replyEmail)) { mainEntity.ReplyTo = new AddressList(); mainEntity.ReplyTo.Add(new MailboxAddress(replyEmail, replyEmail)); } MimeEntity textEntity = mainEntity.ChildEntities.Add(); textEntity.ContentType = MediaType_enum.Text_html; textEntity.ContentTransferEncoding = ContentTransferEncoding_enum.QuotedPrintable; textEntity.DataText = body; //附件 foreach (string attach in attachments) { MimeEntity attachmentEntity = mainEntity.ChildEntities.Add(); attachmentEntity.ContentType = MediaType_enum.Application_octet_stream; attachmentEntity.ContentDisposition = ContentDisposition_enum.Attachment; attachmentEntity.ContentTransferEncoding = ContentTransferEncoding_enum.Base64; FileInfo file = new FileInfo(attach); attachmentEntity.ContentDisposition_FileName = file.Name; attachmentEntity.DataFromFile(attach); } //嵌入图片 foreach (string key in embedImages.Keys) { MimeEntity attachmentEntity = mainEntity.ChildEntities.Add(); attachmentEntity.ContentType = MediaType_enum.Application_octet_stream; attachmentEntity.ContentDisposition = ContentDisposition_enum.Inline; attachmentEntity.ContentTransferEncoding = ContentTransferEncoding_enum.Base64; string imageFile = embedImages[key]; FileInfo file = new FileInfo(imageFile); attachmentEntity.ContentDisposition_FileName = file.Name; //string displayName = Path.GetFileNameWithoutExtension(fileName); attachmentEntity.ContentID = key;//BytesTools.BytesToHex(Encoding.Default.GetBytes(fileName)); attachmentEntity.DataFromFile(imageFile); } return m; }
综合以上两者的发送功能，都可以实现邮件的发送操作，如下界面是发送邮件界面。
3、LumiSoft.NET存储eml邮件文件以及发送eml文件操作
除了上面的发送普通邮件，Lumisoft还支持吧邮件序列号存储到文件(.eml邮件文件)里面，然后也可以通过把文件读取到流里面，进行发送，对于某种场合，可以把邮件存储到eml文件是一个很好的操作。
存储EML文件的相关操作如下所示。
private void btnCreateFile_Click(object sender, EventArgs e) { string attachFile = Path.Combine(Application.StartupPath, "Attachment/Hotel2.png"); List<string> attachments = new List<string>(); attachments.Add(attachFile); string subject = "测试邮件"; string body = "<html>这是一份测试邮件，来自<font color=red><b>LumiSoft.Net</b></font></html>"; string bodyEmbedy = "<html>这是一份测试邮件<img src=\"cid:test.jpg\">，来自<font color=red><b>LumiSoft.Net</b></font></html>"; Dictionary<string, string> embedList = new Dictionary<string, string>(); embedList.Add("test.jpg", "C:\\test.jpg"); //存储为Eml文件 string path = Path.Combine(Application.StartupPath, "Eml"); DirectoryUtil.AssertDirExist(path); string emlFile = string.Format("{0}/{1}.eml", path, DateTime.Now.ToFileTime()); Mime m = Create_Html_Attachment_Image(to, from, from, subject, bodyEmbedy, attachments, embedList); m.ToFile(emlFile); MessageUtil.ShowTips("OK"); }
发送EML文件操作如下所示。
private void btnSendFile_Click(object sender, EventArgs e) { using (SMTP_Client client = new SMTP_Client()) { int smtpPort = smtpUseSsl ? WellKnownPorts.SMTP_SSL : WellKnownPorts.SMTP; client.Connect(smtpServer, smtpPort, smtpUseSsl); client.EhloHelo(smtpServer); //var authhh = new AUTH_SASL_Client_Plain(username, password); //client.Auth(authhh); client.Authenticate(username, password); //string text = client.GreetingText; client.MailFrom(from, -1); client.RcptTo(to); string path = Path.Combine(Application.StartupPath, "Eml"); string emlFile = Directory.GetFiles(path)[0]; var msg = Mail_Message.ParseFromFile(emlFile); MemoryStream stream = new MemoryStream(); msg.ToStream(stream, new MIME_Encoding_EncodedWord(MIME_EncodedWordEncoding.Q, Encoding.UTF8), Encoding.UTF8); stream.Position = 0; client.SendMessage(stream); client.Disconnect(); } MessageUtil.ShowTips("OK"); }
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