Sending email with embeded image

I have written some articles on sending email from .net application. In this article I will show you a tricky way of sending embeded image to your mail.

The trick to embed image is to create an alternative view and to add a linked resource to the alternative view. Alternative views enable you to create different versions of the email message -- typically one in plain text and the other formatted with HTML. These then substitute for the basic msg.Body property.

To do the actual embedding, you need to do a number of things:

• Create an HTML-formatted message.
• Use an <img> tag in the message body.
• For the src attribute of the <img>, point to a content ID (cid). This points to the portion of the message containing the image stream.
• Create an alternative view.
• Create a linkedResource that slurps up the image you want to embed.
• Assign a content ID to the linked resource -- this should match the cid you used in the <img> tag.
• Assign the image's file name to the linked resource.

Here is example code sample:

protected void btnSend_Click(object sender, EventArgs e)
    {
        MailMessage mail = BuildMail();
        SendEMail(mail);
    }

private MailMessage BuildMail()
    {
        string from, to, bcc, cc, subject, body;
        from = "uniquesaiful@gmail.com";   //Email Address of Sender
        to = "tips.asp.net@gmail.com,saifulondotnet@gmail.com,uniquesaiful@gmail.com";   //Email Address of Receiver
        bcc = "";
        cc = "";
        subject = "This is a test email. I am just checking whether email client is working properly.";
 
        string imagePath = Server.MapPath("~") + "\\";
        string fileName = imagePath + "Logo.JPG";
 
        StringBuilder sb = new StringBuilder();
        sb.Append("Hi Scott,<br/>");
        sb.Append("This is a test email. We are testing out email client. Please don't mind.<br/>");
        sb.Append("We are sorry for this unexpected mail to your mail box.<br/>");
        sb.Append("<br/>");
        sb.Append("Thanking you<br/>");
        sb.Append("Tips.Asp.Net");
 
        body = sb.ToString();
 
        AlternateView av = AlternateView.CreateAlternateViewFromString(body, null, MediaTypeNames.Text.Html);
        LinkedResource linkedRes = new LinkedResource(fileName);
        linkedRes.ContentId = "image1";
        linkedRes.ContentType.Name = fileName;
        av.LinkedResources.Add(linkedRes);
 
 
        MailMessage mail = new MailMessage();
        mail.From = new MailAddress(from);
        if (to.Contains(","))
        {
            string[] tos = to.Split(',');
            for (int i = 0; i < tos.Length; i++)
            {
                mail.To.Add(new MailAddress(tos[i]));
            }
        }
        else
        {
            mail.To.Add(new MailAddress(to));
        }
 
        if (!string.IsNullOrEmpty(bcc))
        {
            mail.Bcc.Add(new MailAddress(bcc));
        }
        if (!string.IsNullOrEmpty(cc))
        {
            mail.CC.Add(new MailAddress(cc));
        }
 
        mail.Subject = subject;
        mail.Body = body;
        mail.AlternateViews.Add(av);
        mail.IsBodyHtml = true;
 
        return mail;
    }
 
    private void SendEMail(MailMessage mail)
    {
        SmtpClient client = new SmtpClient();
        client.Host = "smtp.gmail.com";
        client.Port = 587;
        client.EnableSsl = true;
        client.Credentials = new System.Net.NetworkCredential("uniquesaiful", ami@janina.com);
        try
        {
            client.Send(mail);
        }
        catch (Exception ex)
        {
            throw ex;
        }
 
    }