可以使用 for 循环发送批量邮件、批量邮件问题、AWS(amazon) SES

Question

我正在使用 C# 和 .net 进行编码，使用 AWS（亚马逊）SES（简单电子邮件服务）API 一次性发送大约 5000 封邮件，如果发送的邮件数量少于 500，一切正常-600（大约），但如果它更像 5000，它将发送高达 500-600，然后它将停止发送电子邮件。我已经使用datatable来存储数据库中的邮件列表，分配模板正文和主题，然后使用for循环来一一发送电子邮件。我需要知道是编码问题还是 for 循环问题或其他问题？有什么建议对我也有帮助吗？

for (i = 0; i < dtable1.Rows.Count; i++)
    {

        Object a=dtable1.Rows[i]["student_emailid"];
        String TO1=Convert.ToString(a);
        TO1 = TO1.Trim();
        if (TO1.Equals("")) {
            continue;
        }
        const String FROM = "asit@amcsquare.com";   // Replace with your "From" address. This address must be verified.
        String TO = TO1;  // Replace with a "To" address. If your account is still in the
        // sandbox, this address must be verified.

        String SUBJECT = email_subject;
        String BODY = templateBody;


        // Supply your SMTP credentials below. Note that your SMTP credentials are different from your AWS credentials.
        const String SMTP_USERNAME = "XXXXXXXXXXXX";  // Replace with your SMTP username. 
        const String SMTP_PASSWORD = "XXXXXXXXXXXXXXXXXX";  // Replace with your SMTP password.

        // Amazon SES SMTP host name. This example uses the us-west-2 region.
        const String HOST = "email-smtp.us-east-1.amazonaws.com";

        // Port we will connect to on the Amazon SES SMTP endpoint. We are choosing port 587 because we will use
       // STARTTLS to encrypt the connection.
        const int PORT = 587;


        // Create an SMTP client with the specified host name and port.
        using (System.Net.Mail.SmtpClient client = new System.Net.Mail.SmtpClient(HOST, PORT))
        {
            // Create a network credential with your SMTP user name and password.
            client.Credentials = new System.Net.NetworkCredential(SMTP_USERNAME, SMTP_PASSWORD);

                //Use SSL when accessing Amazon SES. The SMTP session will begin on an unencrypted connection, and then 
               //the client will issue a STARTTLS command to upgrade to an encrypted connection using SSL.
            client.EnableSsl = true;
            System.Net.Mail.MailMessage message1 = new System.Net.Mail.MailMessage(FROM, TO, SUBJECT, BODY);

            message1.IsBodyHtml = true;
            client.Send(message1);

        }




    }

Answer 1

我不知道它现在工作的确切原因，但它正在工作。我改变了上面代码的逻辑，它开始工作了。而不是每次都获取SMTP连接，对于之前发送每封邮件，这次我只获取一次smtp连接并使用它一次发送所有批量邮件并开始工作。但问题是发送时间，它是发送所有邮件花费太多。无论如何我也会找到解决方案。

using (System.Net.Mail.SmtpClient client = new System.Net.Mail.SmtpClient(HOST, PORT))
{
    client.Credentials = new System.Net.NetworkCredential(SMTP_USERNAME, SMTP_PASSWORD);
    client.EnableSsl = true;
    for(i=0;i<mail.Count;i++)

            {
                String TO = mail[i];
                System.Net.Mail.MailMessage message1 = new System.Net.Mail.MailMessage(FROM, TO, SUBJECT, BODY);

                message1.IsBodyHtml = true;

                client.DeliveryMethod = SmtpDeliveryMethod.Network;
                client.Send(message1);

            }

    client.Dispose();

}

Label1.Text = mail.Count.ToString() + " mails sent !!";

}