将System.Net.mail.MailMessage保存为.msg文件

Question

我正在构建一个应用程序,我有义务创建一个MailMessage(System.Net.mail.MailMessage)并将其保存在磁盘上,因为.msg扩展名不是.eml

下面是我用来将MailMessage保存为.msg文件的方法:

   public static void Save(MailMessage Message, string FileName)
    {
        Assembly assembly = typeof(SmtpClient).Assembly;
        Type _mailWriterType =
          assembly.GetType("System.Net.Mail.MailWriter");

        using (FileStream _fileStream =
               new FileStream(FileName, FileMode.Create))
        {
            // Get reflection info for MailWriter contructor
            ConstructorInfo _mailWriterContructor =
                _mailWriterType.GetConstructor(
                    BindingFlags.Instance | BindingFlags.NonPublic,
                    null,
                    new Type[] { typeof(Stream) },
                    null);

            // Construct MailWriter object with our FileStream
            object _mailWriter =
              _mailWriterContructor.Invoke(new object[] { _fileStream });

            // Get reflection info for Send() method on MailMessage
            MethodInfo _sendMethod =
                typeof(MailMessage).GetMethod(
                    "Send",
                    BindingFlags.Instance | BindingFlags.NonPublic);

            // Call method passing in MailWriter
            _sendMethod.Invoke(
                Message,
                BindingFlags.Instance | BindingFlags.NonPublic,
                null,
                new object[] { _mailWriter, true },
                null);

            // Finally get reflection info for Close() method on our MailWriter
            MethodInfo _closeMethod =
                _mailWriter.GetType().GetMethod(
                    "Close",
                    BindingFlags.Instance | BindingFlags.NonPublic);

            // Call close method
            _closeMethod.Invoke(
                _mailWriter,
                BindingFlags.Instance | BindingFlags.NonPublic,
                null,
                new object[] { },
                null);
        }
    }

但保存的msg文件没有打开,下面是错误: "无法打开文件xyz.msg.文件文件可能不存在,您可能没有权限打开它或它可能被另一个程序打开.... "

我的问题是:如何将System.Net.mail.MailMessage保存为msg文件？

Answer 1

在这里，瑞安提出了一种简单而有效的方法，无需任何努力即可做到这一点。

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>