Sending email with attachments from C#, attachment

Question

I have a C# application which emails out Excel spreadsheet reports via an Exchange 2007 server using SMTP. These arrive fine for Outlook users, but for Thunderbird and Blackberry users the attachments have been renamed as "Part 1.2".

I found this article which describes the problem, but doesn't seem to give me a workaround. I don't have control of the Exchange server so can't make changes there. Is there anything I can do on the C# end? I have tried using short filenames and HTML encoding for the body but neither made a difference.

My mail sending code is simply this:

public static void SendMail(string recipient, string subject, string body, string attachmentFilename)
{
    SmtpClient smtpClient = new SmtpClient();
    NetworkCredential basicCredential = new NetworkCredential(MailConst.Username, MailConst.Password);
    MailMessage message = new MailMessage();
    MailAddress fromAddress = new MailAddress(MailConst.Username);

    // setup up the host, increase the timeout to 5 minutes
    smtpClient.Host = MailConst.SmtpServer;
    smtpClient.UseDefaultCredentials = false;
    smtpClient.Credentials = basicCredential;
    smtpClient.Timeout = (60 * 5 * 1000);

    message.From = fromAddress;
    message.Subject = subject;
    message.IsBodyHtml = false;
    message.Body = body;
    message.To.Add(recipient);

    if (attachmentFilename != null)
        message.Attachments.Add(new Attachment(attachmentFilename));

    smtpClient.Send(message);
}

Thanks for any help.

Answer 1

Simple code to send email with attachement.

source: http://www.coding-issues.com/2012/11/sending-email-with-attachments-from-c.html

using System.Net;
using System.Net.Mail;

public void email_send()
{
    MailMessage mail = new MailMessage();
    SmtpClient SmtpServer = new SmtpClient("smtp.gmail.com");
    mail.From = new MailAddress("your [e-mail]");
    mail.To.Add("[e-mail]");
    mail.Subject = "Test Mail - 1";
    mail.Body = "mail with attachment";

    System.Net.Mail.Attachment attachment;
    attachment = new System.Net.Mail.Attachment("c:/textfile.txt");
    mail.Attachments.Add(attachment);

    SmtpServer.Port = 587;
    SmtpServer.Credentials = new System.Net.NetworkCredential("your [e-mail]", "your password");
    SmtpServer.EnableSsl = true;

    SmtpServer.Send(mail);

}

Answer 2

private void btnSent_Click(object sender, EventArgs e)
{
    try
    {
        MailMessage mail = new MailMessage();
        SmtpClient SmtpServer = new SmtpClient("smtp.gmail.com");

        mail.From = new MailAddress(txtAcc.Text);
        mail.To.Add(txtToAdd.Text);
        mail.Subject = txtSub.Text;
        mail.Body = txtContent.Text;
        System.Net.Mail.Attachment attachment;
        attachment = new System.Net.Mail.Attachment(txtAttachment.Text);
        mail.Attachments.Add(attachment);

        SmtpServer.Port = 587;
        SmtpServer.Credentials = new System.Net.NetworkCredential(txtAcc.Text, txtPassword.Text);

        SmtpServer.EnableSsl = true;

        SmtpServer.Send(mail);
        MessageBox.Show("mail send");
    }
    catch (Exception ex)
    {
        MessageBox.Show(ex.ToString());
    }
}

private void button1_Click(object sender, EventArgs e)
{
    MailMessage mail = new MailMessage();
    openFileDialog1.ShowDialog();
    System.Net.Mail.Attachment attachment;
    attachment = new System.Net.Mail.Attachment(openFileDialog1.FileName);
    mail.Attachments.Add(attachment);
    txtAttachment.Text =Convert.ToString (openFileDialog1.FileName);
}

Answer 3

Try this:

private void btnAtt_Click(object sender, EventArgs e) {

    openFileDialog1.ShowDialog();
    Attachment myFile = new Attachment(openFileDialog1.FileName);

    MyMsg.Attachments.Add(myFile);


}

Answer 4

Completing the solution of Ranadheer, using Server.MapPath to locate the file

System.Net.Mail.Attachment attachment;
attachment = New System.Net.Mail.Attachment(Server.MapPath("~/App_Data/hello.pdf"));
mail.Attachments.Add(attachment);

Answer 5

I tried the code provided by Ranadheer Reddy (above) and it worked great. If you’re using a company computer that has a restricted server you may need to change the SMTP port to 25 and leave your username and password blank since they will auto fill by your admin.

Originally, I tried using EASendMail from the nugent package manager, only to realize that it’s a pay for version with 30-day trial. Don’t waist your time with it unless you plan on buying it. I noticed the program ran much faster using EASendMail, but for me, free trumped fast.

Just my 2 cents worth.

Answer 6

I've made a short code to do that and I want to share it with you.

Here the main code:

public void Send(string from, string password, string to, string Message, string subject, string host, int port, string file)
{

  MailMessage email = new MailMessage();
  email.From = new MailAddress(from);
  email.To.Add(to);
  email.Subject = subject;
  email.Body = Message;
  SmtpClient smtp = new SmtpClient(host, port);
  smtp.UseDefaultCredentials = false;
  NetworkCredential nc = new NetworkCredential(from, password);
  smtp.Credentials = nc;
  smtp.EnableSsl = true;
  email.IsBodyHtml = true;
  email.Priority = MailPriority.Normal;
  email.BodyEncoding = Encoding.UTF8;

  if (file.Length > 0)
  {
    Attachment attachment;
    attachment = new Attachment(file);
    email.Attachments.Add(attachment);
  }

  // smtp.Send(email);
  smtp.SendCompleted += new SendCompletedEventHandler(SendCompletedCallBack);
  string userstate = "sending ...";
  smtp.SendAsync(email, userstate);
}

private static void SendCompletedCallBack(object sender,AsyncCompletedEventArgs e) {
  string result = "";
  if (e.Cancelled)
  {    
    MessageBox.Show(string.Format("{0} send canceled.", e.UserState),"Message",MessageBoxButtons.OK,MessageBoxIcon.Information);
  }
  else if (e.Error != null)
  {
    MessageBox.Show(string.Format("{0} {1}", e.UserState, e.Error), "Message", MessageBoxButtons.OK, MessageBoxIcon.Information);
  }
  else {
    MessageBox.Show("your message is sended", "Message", MessageBoxButtons.OK, MessageBoxIcon.Information);
  }

}

In your button do stuff like this
you can add your jpg or pdf files and more .. this is just an example

using (OpenFileDialog attachement = new OpenFileDialog()
{
  Filter = "Exel Client|*.png",
  ValidateNames = true
})
{
if (attachement.ShowDialog() == DialogResult.OK)
{
  Send("[e-mail]", "gmail_password", 
       "[e-mail]", "just smile ", "mail with attachement",
       "smtp.gmail.com", 587, attachement.FileName);

}
}