C# 如何将 MailMessage 对象作为 *.eml 或 *.msg 文件保存到磁盘

How to save MailMessage object to disk as *.eml or *.msg file

提问by ashwnacharya

How do I save MailMessage object to the disk? The MailMessage object does not expose any Save() methods.

如何将 MailMessage 对象保存到磁盘？MailMessage 对象不公开任何 Save() 方法。

I dont have a problem if it saves in any format, *.eml or *.msg. Any idea how to do this?

如果它以任何格式保存，*.eml 或 *.msg，我没有问题。知道如何做到这一点吗？

采纳答案by Ryan Versaw

For simplicity, I'll just quote an explanation from a Connect item:

为简单起见，我将引用Connect 项的解释：

You can actually configure the SmtpClient to send emails to the file system instead of the network. You can do this programmatically using the following code:

SmtpClient client = new SmtpClient("mysmtphost");
client.DeliveryMethod = SmtpDeliveryMethod.SpecifiedPickupDirectory;
client.PickupDirectoryLocation = @"C:\somedirectory";
client.Send(message);

You can also set this up in your application configuration file like this:

您实际上可以配置 SmtpClient 将电子邮件发送到文件系统而不是网络。您可以使用以下代码以编程方式执行此操作：

SmtpClient client = new SmtpClient("mysmtphost");
client.DeliveryMethod = SmtpDeliveryMethod.SpecifiedPickupDirectory;
client.PickupDirectoryLocation = @"C:\somedirectory";
client.Send(message);

您还可以在您的应用程序配置文件中进行设置，如下所示：

 <configuration>
     <system.net>
         <mailSettings>
             <smtp deliveryMethod="SpecifiedPickupDirectory">
                 <specifiedPickupDirectory pickupDirectoryLocation="C:\somedirectory" />
             </smtp>
         </mailSettings>
     </system.net>
 </configuration>

After sending the email, you should see email files get added to the directory you specified. You can then have a separate process send out the email messages in batch mode.

发送电子邮件后，您应该会看到电子邮件文件被添加到您指定的目录中。然后，您可以让单独的进程以批处理模式发送电子邮件。

You should be able to use the empty constructor instead of the one listed, as it won't be sending it anyway.

您应该能够使用空构造函数而不是列出的构造函数，因为无论如何它都不会发送它。

回答by saille

Here's an extension method to convert a MailMessage to a stream containing the EML data. Its obviously a bit of a hack as it uses the file system, but it works.

这是将 MailMessage 转换为包含 EML 数据的流的扩展方法。由于它使用文件系统，这显然有点黑客，但它可以工作。

public static void SaveMailMessage(this MailMessage msg, string filePath)
{
    using (var fs = new FileStream(filePath, FileMode.Create))
    {
        msg.ToEMLStream(fs);
    }
}

/// <summary>
/// Converts a MailMessage to an EML file stream.
/// </summary>
/// <param name="msg"></param>
/// <returns></returns>
public static void ToEMLStream(this MailMessage msg, Stream str)
{
    using (var client = new SmtpClient())
    {
        var id = Guid.NewGuid();

        var tempFolder = Path.Combine(Path.GetTempPath(), Assembly.GetExecutingAssembly().GetName().Name);

        tempFolder = Path.Combine(tempFolder, "MailMessageToEMLTemp");

        // create a temp folder to hold just this .eml file so that we can find it easily.
        tempFolder = Path.Combine(tempFolder, id.ToString());

        if (!Directory.Exists(tempFolder))
        {
            Directory.CreateDirectory(tempFolder);
        }

        client.UseDefaultCredentials = true;
        client.DeliveryMethod = SmtpDeliveryMethod.SpecifiedPickupDirectory;
        client.PickupDirectoryLocation = tempFolder;
        client.Send(msg);

        // tempFolder should contain 1 eml file

        var filePath = Directory.GetFiles(tempFolder).Single();

        // stream out the contents
        using (var fs = new FileStream(filePath, FileMode.Open))
        {
            fs.CopyTo(str);
        }

        if (Directory.Exists(tempFolder))
        {
            Directory.Delete(tempFolder, true);
        }
    }
}

You can then take the stream thats returned and do as you want with it, including saving to another location on disk or storing in a database field, or even emailing as an attachment.

然后，您可以获取返回的流并随心所欲地使用它，包括保存到磁盘上的另一个位置或存储在数据库字段中，甚至作为附件通过电子邮件发送。

回答by Gregory Way

For one reason or another the client.send failed (right after an actual send using that method) so I plugged in good 'ole CDO and ADODB stream. I also had to load CDO.message with a template.eml before setting the .Message values. But it works.

出于某种原因，client.send 失败（在使用该方法实际发送之后），所以我插入了好的 'ole CDO 和 ADODB 流。在设置 .Message 值之前，我还必须使用 template.eml 加载 CDO.message。但它有效。

Since the above one is C here is one for VB

由于上面的一个是C，这里是VB的一个

    MyMessage.From = New Net.Mail.MailAddress(mEmailAddress)
    MyMessage.To.Add(mToAddress)
    MyMessage.Subject = mSubject
    MyMessage.Body = mBody

    Smtp.Host = "------"
    Smtp.Port = "2525"
    Smtp.Credentials = New NetworkCredential(------)

    Smtp.Send(MyMessage)        ' Actual Send

    Dim oldCDO As CDO.Message
    oldCDO = MyLoadEmlFromFile("template.eml")  ' just put from, to, subject blank. leave first line blank
    oldCDO.To = mToAddress
    oldCDO.From = mEmailAddress
    oldCDO.Subject = mSubject
    oldCDO.TextBody = mBody
    oldCDO.HTMLBody = mBody
    oldCDO.GetStream.Flush()
    oldCDO.GetStream.SaveToFile(yourPath)

回答by Naveen

If you are using Mailkit. Just write below code

如果您使用的是Mailkit。直接写下面的代码

string fileName = "your filename full path";
MimeKit.MimeMessage message = CreateMyMessage ();
message.WriteTo(fileName);