邮件正文为图片

SmtpClient smtp = new SmtpClient();
            smtp.DeliveryMethod = SmtpDeliveryMethod.Network;
            smtp.Host = "smtp.163.com";
            smtp.Credentials = new NetworkCredential("renzhijie1111", "renzhijie");

            MailMessage mm = new MailMessage();
            mm.From = new MailAddress("renzhijie1111@163.com", "无敌任志杰测试");
            mm.To.Add("renzhijie1990@vip.qq.com");

            mm.Subject = "发送带图片邮件";

            string plainTextBody = "如果你邮件客户端不支持HTML格式，或者你切换到“普通文本”视图，将看到此内容";
            mm.AlternateViews.Add(AlternateView.CreateAlternateViewFromString(plainTextBody, null, "text/plain"));

            ////HTML格式邮件的内容
            string htmlBodyContent = "如果你的看到<b>这个</b>， 说明你是在以 <span style=\"color:red\">HTML</span> 格式查看邮件<br><br>";
            htmlBodyContent += "<a href=\"http://www.vayule.com//%22%3EVA娱乐网</a> <img src=\"cid:weblogo\">";   //注意此处嵌入的图片资源
            AlternateView htmlBody = AlternateView.CreateAlternateViewFromString(htmlBodyContent, null, "text/html");

          
            LinkedResource lrImage = new LinkedResource(@"d:\1.jpg", "image/gif");
            lrImage.ContentId = "weblogo"; //此处的ContentId 对应 htmlBodyContent 内容中的 cid:  ，如果设置不正确，请不会显示图片
            htmlBody.LinkedResources.Add(lrImage);

            mm.AlternateViews.Add(htmlBody);

            ////要求回执的标志
            mm.Headers.Add("Disposition-Notification-To", "renzhijie1111@163.com");

            ////自定义邮件头
            mm.Headers.Add("X-Website", "http://www.vayule.com/");

            ////针对 LOTUS DOMINO SERVER，插入回执头
            mm.Headers.Add("ReturnReceipt", "1");

            mm.Priority = MailPriority.Normal; //优先级
            mm.ReplyTo = new MailAddress("renzhijie1111@163.com", "我自己");

            ////如果发送失败，SMTP 服务器将发送 失败邮件告诉我
            mm.DeliveryNotificationOptions = DeliveryNotificationOptions.OnFailure;

            ////异步发送完成时的处理事件
            smtp.SendCompleted += new SendCompletedEventHandler(smtp_SendCompleted);

            ////开始异步发送
            smtp.SendAsync(mm, null);





void smtp_SendCompleted(object sender, AsyncCompletedEventArgs e)
        {
            if (e.Cancelled)
            {
                MessageBox.Show("发送被取消");
            }
            else
            {
                if (e.Error == null)
                {
                    MessageBox.Show("发送成功");
                }
                else
                {
                    MessageBox.Show("发送失败： " + e.Error.Message);
                }
            }
        }