c# - System.Net.Mail.MailMessage电子邮件作为Microsoft Dynamics CRM 2011中传出电子邮件的附件

Question

如何将电子邮件作为MSG文件附加到CRM 2011中的外发电子邮件中？

我已经创建了电子邮件的html附件，可以，但是必须在浏览器中查看html附件； Outlook中的预览不显示图像。

我的问题是CRM中的ActivityMimeAttachment实体要求主体为Base64字符串，如果它是html字符串作为附件，则可以：

        // UnicodeEncoding had to be used as there were problems with 
        // special char in ASCII
        var bodyArray = System.Text.UnicodeEncoding.Unicode.GetBytes(body);
        body = System.Convert.ToBase64String(bodyArray);
        return body;

如何使用从 System.Net.Mail.MailMessage创建的MSG文件作为附件，或者如何将 System.Net.Mail.MailMessage电子邮件转换为Base64String？

Answer 1

我发现了这个codeproject article

它使用反射通过非公开的MailWriter类型保存它。这种方式很脏，但是除了in this answer描述的官方方式之外

public static class MailMessageExt
{
    public static void Save(this 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);
        }
    }
}

然后

MailMessage _testMail = new MailMessage();
_testMail.Body = "This is a test email";
_testMail.To.Add(new MailAddress("email@domain.com"));
_testMail.From = new MailAddress("sender@domain.com");
_testMail.Subject = "Test email";
_testMail.Save(@"c:\testemail.eml");
var bytes = System.IO.File.ReadAllBytes(@"c:\testemail.eml");
var bodyArray = System.Text.UnicodeEncoding.Unicode.GetBytes(bytes);
var body = System.Convert.ToBase64String(bodyArray);