使用 Williwyg 的答案这个问题，我想知道它是否可以在asp.net中工作。经过一些修改就可以工作了。此代码片段将创建一封带有附件的电子邮件，并将其转换为eml归档并发送给客户。
using System.Web;
using System.Text;
using System.IO;
using System.Net.Mail;
using System.Reflection;
protected void Button1_Click(object sender, EventArgs e)
{
//create an email
MailMessage message = new MailMessage();
message.From = new MailAddress("[email protected]", "MyCompany");
message.Subject = "Email subject goes here";
message.IsBodyHtml = true;
message.Body = "<html><head></head><body><font size=\"3\" color=\"#ff0000\">HTML formatted email body.</body></html>";
//add the attachment
message.Attachments.Add(new Attachment(Server.MapPath("test.pdf")));
//get the message as byte array
byte[] bin = getEmailAsEML(message);
//send the email to the client as eml
Response.ClearHeaders();
Response.Clear();
Response.Buffer = true;
Response.ContentType = "message/rfc822";
Response.AddHeader("content-length", bin.Length.ToString());
Response.AddHeader("content-disposition", "attachment; filename=\"email.eml\"");
Response.OutputStream.Write(bin, 0, bin.Length);
Response.Flush();
HttpContext.Current.ApplicationInstance.CompleteRequest();
}
public byte[] getEmailAsEML(MailMessage message)
{
using (MemoryStream ms = new MemoryStream())
{
var binaryWriter = new BinaryWriter(ms);
//Write the Unsent header to the file so the mail client knows this mail must be presented in "New message" mode
binaryWriter.Write(Encoding.UTF8.GetBytes("X-Unsent: 1" + Environment.NewLine));
var assembly = typeof(SmtpClient).Assembly;
var mailWriterType = assembly.GetType("System.Net.Mail.MailWriter");
// Get reflection info for MailWriter contructor
var mailWriterContructor = mailWriterType.GetConstructor(BindingFlags.Instance | BindingFlags.NonPublic, null, new[] { typeof(Stream) }, null);
// Construct MailWriter object with our FileStream
var mailWriter = mailWriterContructor.Invoke(new object[] { ms });
// Get reflection info for Send() method on MailMessage
var sendMethod = typeof(MailMessage).GetMethod("Send", BindingFlags.Instance | BindingFlags.NonPublic);
sendMethod.Invoke(message, BindingFlags.Instance | BindingFlags.NonPublic, null, new object[] { mailWriter, true, true }, null);
// Finally get reflection info for Close() method on our MailWriter
var closeMethod = mailWriter.GetType().GetMethod("Close", BindingFlags.Instance | BindingFlags.NonPublic);
// Call close method
closeMethod.Invoke(mailWriter, BindingFlags.Instance | BindingFlags.NonPublic, null, new object[] { }, null);
return ms.ToArray();
}
}
