尝试这个
string htmlBody = "<html><body><h1>Picture</h1><br><img src="cid:filename"></body></html>"; AlternateView avHtml = AlternateView.CreateAlternateViewFromString (htmlBody, null, MediaTypeNames.Text.Html); linkedResource inline = new linkedResource("filename.jpg", MediaTypeNames.Image.Jpeg); inline.ContentId = Guid.NewGuid().ToString(); avHtml.linkedResources.Add(inline); MailMessage mail = new MailMessage(); mail.AlternateViews.Add(avHtml); Attachment att = new Attachment(filePath); att.ContentDisposition.Inline = true; mail.From = from_email; mail.To.Add(data.email); mail.Subject = "Client: " + data.client_id + " Has Sent You A Screenshot"; mail.Body = String.Format( "<h3>Client: " + data.client_id + " Has Sent You A Screenshot</h3>" + @"<img src=""cid:{0}"" />", att.ContentId); mail.IsBodyHtml = true; mail.Attachments.Add(att);
