How to send email with embedded image using Mail function in C#?

Question

All what I want is sending an email with embedded image. I am struggling with it and I don't know why I could not get it. The system sends that email but without showing the image and here's a snapshot of the result:

Could you please help me in modifying the code shown below to deal with sending that image? Let us assume that we have any image.

C# Code:

protected void Page_Load(object sender, EventArgs e)
    {
        Send();
    }


    protected void SendEmail(string toAddresses, string fromAddress, string MailSubject, string MessageBody, bool isBodyHtml, AlternateView av)
    {
        SmtpClient sc = new SmtpClient("MailAddress");
        try
        {
            MailMessage msg = new MailMessage();
            msg.From = new MailAddress("test@mailAddress.com", "Test Sys");   

            //QuizLink is appSetting inside your web config
            string newLink = System.Configuration.ConfigurationManager.AppSettings["QuizLink"].ToString();


            msg.Bcc.Add(toAddresses);
            msg.Subject = MailSubject;
            msg.Body = MessageBody;
            msg.IsBodyHtml = isBodyHtml;
            msg.AlternateViews.Add(av);
            sc.Send(msg);
        }
        catch (Exception ex)
        {
            throw ex;
        }

    }

    protected void SendEmailTOAllUser()
    {
        string connString = "Data Source=localhost;Initial Catalog=TestDB;Integrated Security=True";

        using (SqlConnection conn = new SqlConnection(connString))
        {
            var sbEmailAddresses = new System.Text.StringBuilder(2000);
            string quizid = "";

            // Open DB connection.
            conn.Open();

            string cmdText = "SELECT MIN (QuizID) As mQuizID FROM dbo.QUIZ WHERE IsSent <> 1";
            using (SqlCommand cmd = new SqlCommand(cmdText, conn))
            {
                SqlDataReader reader = cmd.ExecuteReader();
                if (reader != null)
                {
                    while (reader.Read())
                    {
                        // There is only 1 column, so just retrieve it using the ordinal position
                        quizid = reader["mQuizID"].ToString();

                    }
                }
                reader.Close();
            }

            string cmdText2 = "SELECT Username FROM dbo.employee";
            using (SqlCommand cmd = new SqlCommand(cmdText2, conn))
            {
                SqlDataReader reader = cmd.ExecuteReader();
                if (reader != null)
                {
                    while (reader.Read())
                    {
                        var sName = reader.GetString(0);
                        if (!string.IsNullOrEmpty(sName))
                        {
                            if (sbEmailAddresses.Length != 0)
                            {
                                sbEmailAddresses.Append(",");
                            }
                            // Just use the ordinal position for the user name since there is only 1 column
                            sbEmailAddresses.Append(sName).Append("@mailAddress.com");
                        }
                    }
                }
                reader.Close();
            }

            string cmdText3 = "UPDATE dbo.Quiz SET IsSent = 1 WHERE QuizId = @QuizID";
            using (SqlCommand cmd = new SqlCommand(cmdText3, conn))
            {
                // Add the parameter to the command
                var oParameter = cmd.Parameters.Add("@QuizID", SqlDbType.Int);

                var sEMailAddresses = sbEmailAddresses.ToString();
                string link = "<a href='http://localhost/test.aspx?testid=" + quizid + "'> Click here to participate </a>";
                string body = @"................";
                AlternateView av = AlternateView.CreateAlternateViewFromString(body, null, MediaTypeNames.Text.Html);
                LinkedResource lr = new LinkedResource("contactUs.gif", MediaTypeNames.Image.Gif);
                lr.ContentId="image1";
                av.LinkedResources.Add(lr);


                int sendCount = 0;
                List<string> addressList = new List<string>(sEMailAddresses.Split(','));
                StringBuilder addressesToSend = new StringBuilder();

                if (!string.IsNullOrEmpty(quizid))
                {
                    for (int userIndex = 0; userIndex < addressList.Count; userIndex++)
                    {
                        sendCount++;
                        if (addressesToSend.Length > 0)
                            addressesToSend.Append(",");

                        addressesToSend.Append(addressList[userIndex]);
                        if (sendCount == 10 || userIndex == addressList.Count - 1)
                        {
                            SendEmail(addressesToSend.ToString(), "", "........", body, true, av);
                            addressesToSend.Clear();
                            sendCount = 0;
                        }
                    }

                    // Update the parameter for the current quiz
                    oParameter.Value = quizid;
                    // And execute the command
                    cmd.ExecuteNonQuery();
                }

            }
            conn.Close();
        }
    }

Answer 1

Throughout all of your exapmle it seem like you are sending the image like this /somefolder/image.jpg you can not send it this way since the user is reading the image from another domain name which is most likely not yours so if you look at the source code of you image you would see that it different from on you use.

you should send the image link like this

<img src='http://www.mydomainname.com/fulladdress/someimage.png usemap' ='#clickMap'>