Question

I am using the SmtpClient in C# and I will be sending to potentially 100s of email addresses. I don’t want to have to loop through each one and send them an individual email.

I know it is possible to only send the message once but I don’t want the email from address to display the 100s of other email addresses like this:

Bob Hope; Brain Cant; Roger Rabbit;Etc Etc

Is it possible to send the message once and ensure that only the recipient’s email address is displayed in the from part of the email?

Answer 1

Ever heard of BCC (Blind Carbon Copy) ? 🙂

If you can make sure that your SMTP Client can add the addresses as BCC, then your problem will be solved 🙂

There seems to be a Blind Carbon Copy item in the MailMessage class

http://msdn.microsoft.com/en-us/library/system.net.mail.mailmessage.aspx

http://msdn.microsoft.com/en-us/library/system.net.mail.mailmessage.bcc.aspx

Here is a sample i got from MSDN

public static void CreateBccTestMessage(string server)
        {
            MailAddress from = new MailAddress("[e-mail]", "Ben Miller");
            MailAddress to = new MailAddress("[e-mail]", "Jane Clayton");
            MailMessage message = new MailMessage(from, to);
            message.Subject = "Using the SmtpClient class.";
            message.Body = @"Using this feature, you can send an e-mail message from an application very easily.";
            MailAddress bcc = new MailAddress("[e-mail]");

                //This is what you need
                message.Bcc.Add(bcc);
                SmtpClient client = new SmtpClient(server);
                client.Credentials = CredentialCache.DefaultNetworkCredentials;
                Console.WriteLine("Sending an e-mail message to {0} and {1}.", 
                    to.DisplayName, message.Bcc.ToString());
          try {
            client.Send(message);
          }  
          catch (Exception ex) {
            Console.WriteLine("Exception caught in CreateBccTestMessage(): {0}", 
                        ex.ToString() );
          }
        }