Email Attachment from memory stream is coming as blank in C#

Question

I am able to send an attachment in a mail but the attachment content is blank and size is being shown as 0 bytes.

After doing some search over the internet found that we need to reset the memory stream position to 0 in order to start from start.

I tried that as well but it seems it is not working. Can you please help?

Please find below my code snippet:

NOTE: I am able to save the workbook and Data is present in the saved workbook.

        MemoryStream memoryStream = new MemoryStream();

        StreamWriter writer = new StreamWriter(memoryStream);
        writer.Write(xlWorkbook);
        writer.Flush();
        memoryStream.Position = 0;
        MailMessage mail = new MailMessage();
        SmtpClient SmtpServer = new SmtpClient("smtpclient");
        mail.From = new MailAddress("from@gmail.com");
        mail.To.Add("To@gmail.com");
        mail.Subject = "Entry";
        mail.Body = "Hello, PFA ";
        System.Net.Mail.Attachment attachment;

        attachment = new System.Net.Mail.Attachment(memoryStream,"xls");
        attachment.ContentDisposition.FileName = "Input" + DateTime.Now.ToString("yyyyMMdd_hhss") + ".xls";
        mail.Attachments.Add(attachment);
        SmtpServer.Port = 465;
        SmtpServer.UseDefaultCredentials = false;
        SmtpServer.Credentials = new System.Net.NetworkCredential("Username", "password");
        SmtpServer.EnableSsl = true;
        SmtpServer.Send(mail);
        writer.Dispose();

Do you know that the XLS file is being properly read? What is the position after the flush? — Virmundi, Feb 11 '15 at 13:34
Last diagnostic question, what happens if you Seek to 0 rather than Position = 0? Like memStream.Seek(0, SeekOrigin.Begin); — Virmundi, Feb 11 '15 at 13:52
I tried that as well , still i am getting the same blank attachment in the email. — Vineet More, Feb 12 '15 at 06:42
Check tranquil tarn answer on http://stackoverflow.com/questions/5336239/how-to-attach-a-file-from-memorystream-to-a-mailmessage-in-c-sharp You need to use stream.Position = 0; — dijam, Nov 01 '16 at 21:27

score 5 · Accepted Answer · answered Feb 12 '15 at 13:46

5

I think the attachment is confusing the mail system. Microsoft's recommendation is to specify the content type as an octet. Below is a replacement for initializing the attachment. The reset of your code looks fine.

string filename = "Input" + DateTime.Now.ToString("yyyyMMdd_hhss") + ".xls";
attachment = new System.Net.Mail.Attachment(memoryStream, filename, MediaTypeNames.Application.Octet);

answered Feb 12 '15 at 13:46

Virmundi

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See this: https://stackoverflow.com/questions/3710677/email-attachment-from-the-memorystream-comes-empty?rq=1 – Dan_J Jul 07 '17 at 10:48

Email Attachment from memory stream is coming as blank in C#

1 Answers1