C# 如何使用图像附件向多个ID发送邮件？

我正在向这4个ID发送邮件以及图像附件

带有图像的文本将到达所有4个EmailID

仅为emailid显示图像（大小700kb）Xyz@gmail.com但对于其余部分，emailids文本正在显示。图像也已到达，但未打开（显示）（图像大小（171B）（实际大小700kb））

仅对于第一个emailid，尝试从邮件中打开图像时会显示图像

所有4个EmailID都有4个foreach循环

尝试打开图像时，我得到以下信息：

代码：

下面的代码在尝试打开附加的图像时显示邮件中的图像Xyz@gmail.com

Email------>Say Xyz@gmail.com
Email1----->Say Abc@gmail.com
Email2----->Say cid@gmail.com
Email3----->Say wer@gmail.com

foreach (string email in emails)
            {

                string SendEmail = email;
                idno = idno + 1;

                try
                {

                    MailMessage message = new MailMessage(from, SendEmail, txtsubject.Text, myString);
                    message.From = new MailAddress(from, fromname);
                    message.DeliveryNotificationOptions = DeliveryNotificationOptions.OnSuccess;
                    message.DeliveryNotificationOptions = DeliveryNotificationOptions.OnFailure;
                    message.Headers.Add("Disposition-Notification-To", from);
                    message.IsBodyHtml = true;
                    if (fuAttach.HasFile)
                    {
                        filename = Path.GetFileName(fuAttach.PostedFile.FileName);
                        fuAttach.SaveAs(Server.MapPath("~/expo_crm/Attachments/" + filename));
                        Attachment data = new Attachment(fuAttach.PostedFile.InputStream, filename);
                        message.Attachments.Add(data);
                    }
                    smtp.Send(message);

                    object userid = user_ids[idno];
                    // int tst = Convert.ToInt(userid);

                    // int uid = Convert.ToInt16(user_ids[idno]);
                    Int32 uid = Convert.ToInt32(user_ids[idno]);
                    sent_user_ids.Add(uid);
                }

                catch (Exception ex)
                {

                    errorno++;
                    object userid = user_ids[idno];
                    // int tst = Convert.ToInt(userid);
                   // int uid = Convert.ToInt16(user_ids[idno]);

                    Int32 uid = Convert.ToInt32(user_ids[idno]);
                    Notsent_user_ids.Add(uid);
                }
            }

下面的代码不显示邮件中的图像Abc@gmail.com

Email------>Say Xyz@gmail.com
Email1----->Say Abc@gmail.com
Email2----->Say cid@gmail.com
Email3----->Say wer@gmail.com

foreach (string email in emails)
            {

                string SendEmail = email;
                idno = idno + 1;

                try
                {

                    MailMessage message = new MailMessage(from, SendEmail, txtsubject.Text, myString);
                    message.From = new MailAddress(from, fromname);
                    message.DeliveryNotificationOptions = DeliveryNotificationOptions.OnSuccess;
                    message.DeliveryNotificationOptions = DeliveryNotificationOptions.OnFailure;
                    message.Headers.Add("Disposition-Notification-To", from);
                    message.IsBodyHtml = true;
                    if (fuAttach.HasFile)
                    {
                        filename = Path.GetFileName(fuAttach.PostedFile.FileName);
                        fuAttach.SaveAs(Server.MapPath("~/expo_crm/Attachments/" + filename));
                        Attachment data = new Attachment(fuAttach.PostedFile.InputStream, filename);
                        message.Attachments.Add(data);
                    }
                    smtp.Send(message);

                    object userid = user_ids[idno];
                    // int tst = Convert.ToInt(userid);

                    // int uid = Convert.ToInt16(user_ids[idno]);
                    Int32 uid = Convert.ToInt32(user_ids[idno]);
                    sent_user_ids.Add(uid);
                }

                catch (Exception ex)
                {

                    errorno++;
                    object userid = user_ids[idno];
                    // int tst = Convert.ToInt(userid);
                   // int uid = Convert.ToInt16(user_ids[idno]);

                    Int32 uid = Convert.ToInt32(user_ids[idno]);
                    Notsent_user_ids.Add(uid);
                }
            }

---

我不知道第二个

foreach

循环有什么问题，我在这里没有提供的另外两个

foreach

循环也是如此。

我认为问题在于，您一遍又一遍地从同一个流中读取数据，除非在第一次尝试之后，您从流的末尾读取数据，因此没有数据

一个快速解决方案是在发送每封电子邮件之前查找流的开头：

idno = -1;
            foreach (string email in emails1)
            {
                string MyEmail1 = email;
                idno = idno + 1;
                if (MyEmail1 != "N/A")
                {
                    try
                    {

                        MailMessage message = new MailMessage(from, MyEmail1, txtsubject.Text, myString);
                        message.From = new MailAddress(from, fromname);
                        message.DeliveryNotificationOptions = DeliveryNotificationOptions.OnSuccess;
                        message.DeliveryNotificationOptions = DeliveryNotificationOptions.OnFailure;
                        message.Headers.Add("Disposition-Notification-To", from);
                        message.IsBodyHtml = true;
                        if (fuAttach.HasFile)
                        {
                            filename = Path.GetFileName(fuAttach.PostedFile.FileName);
                            fuAttach.SaveAs(Server.MapPath("~/expo_crm/Attachments/" + filename));//added by chetan
                            Attachment data = new Attachment(fuAttach.PostedFile.InputStream, filename);
                            message.Attachments.Add(data);
                        }
                        smtp.Send(message);
                        sent1++;




                    }

                    catch (Exception ex)
                    {
                        object userid = user_ids[idno];
                        // int tst = Convert.ToInt(userid);
                        // int uid = Convert.ToInt16(user_ids[idno]);
                        Int32 uid = Convert.ToInt32(user_ids[idno]);
                        notsend1.Add(uid);
                    }
                }
            }

如果您曾经使代码并行（即多线程），请注意，您将无法使用单个流来实现此目的。还请注意，并非所有流都是可查找的（您可以检查它们的

CanSeek

属性）

---

如果处理的是不可查找的流，则可以（取决于文件大小、内存限制等）将其复制到

MemoryStream

或将其保存到文件中，并为每封电子邮件读取该文件。请参阅。

我认为问题在于，您一遍又一遍地从同一个流中读取数据，除非在第一次尝试后，您从流的末尾读取数据，因此无法获得任何数据

一个快速解决方案是在发送每封电子邮件之前查找流的开头：

idno = -1;
            foreach (string email in emails1)
            {
                string MyEmail1 = email;
                idno = idno + 1;
                if (MyEmail1 != "N/A")
                {
                    try
                    {

                        MailMessage message = new MailMessage(from, MyEmail1, txtsubject.Text, myString);
                        message.From = new MailAddress(from, fromname);
                        message.DeliveryNotificationOptions = DeliveryNotificationOptions.OnSuccess;
                        message.DeliveryNotificationOptions = DeliveryNotificationOptions.OnFailure;
                        message.Headers.Add("Disposition-Notification-To", from);
                        message.IsBodyHtml = true;
                        if (fuAttach.HasFile)
                        {
                            filename = Path.GetFileName(fuAttach.PostedFile.FileName);
                            fuAttach.SaveAs(Server.MapPath("~/expo_crm/Attachments/" + filename));//added by chetan
                            Attachment data = new Attachment(fuAttach.PostedFile.InputStream, filename);
                            message.Attachments.Add(data);
                        }
                        smtp.Send(message);
                        sent1++;




                    }

                    catch (Exception ex)
                    {
                        object userid = user_ids[idno];
                        // int tst = Convert.ToInt(userid);
                        // int uid = Convert.ToInt16(user_ids[idno]);
                        Int32 uid = Convert.ToInt32(user_ids[idno]);
                        notsend1.Add(uid);
                    }
                }
            }

如果您曾经使代码并行（即多线程），请注意，您将无法使用单个流来实现此目的。还请注意，并非所有流都是可查找的（您可以检查它们的

CanSeek

属性）

---

如果处理的是不可查找的流，则可以（取决于文件大小、内存限制等）将其复制到

MemoryStream

或将其保存到文件中，并为每封电子邮件读取该文件。请参阅。

@John..是的..我试图查看图像，但它没有显示…我只是再次读取了您的代码。你能告诉我第二次迭代（即第二封电子邮件）的

fuAttach.PostedFile.InputStream.Position的值是多少吗？@John它显示了一些数字726414@John我应该共享Sendmail的完整代码吗？@John..是的..我试图查看图像，但它没有显示…我只是再次阅读了您的代码。你能告诉我第二次迭代（即第二封电子邮件）的
fuAttach.PostedFile.InputStream.Position的值是多少吗？@John它显示了一些数字726414@John我应该共享Sendmail的完整代码吗？