Question

I attach some files to the Email through the following method :

if (rad_upload.UploadedFiles != null && rad_upload.UploadedFiles.Count > 0)
{

    foreach (UploadedFile file in rad_upload.UploadedFiles)
    {
        Attachment f = new Attachment(file.InputStream, 
                                      MediaTypeNames.Application.Octet);
        attach.Add(f);
    }
}

Contact_List.sendMail(mail, lbl_depEmailValue.Text.TrimEnd(), 
password, txt_sub.Text, msg.ToString(), int.Parse(dep.Main_code.ToString()),
attach);

---

And in the sendMail method :

if (attachments != null && attachments.Count > 0)
{
    foreach (Attachment a in attachments)
    {
        mail.Attachments.Add(a);
    }
}

---

Every thing goes okay , but i wanna to know how to let the uploaded file opened with its convenient program automatically .

For example :

The pdf files opened automatically with acrobat reader if installed when double clicking on the file.

Answer 1

I think you have to set the ContentType of yours Attachments

MSDN source