从ASP.NET网站发送的电子邮件中未加载图片和CSS

Question

In my asp.net website I have functionality to send HTML enabled emails. These emails are sent using SMTP and these emails contain images and are also referring css files. The problem is that images in the received emails are not displaying when opened in gmail, yahoo and other domains. The same problem is occurring for the css code/files that I have used in the HTML of email.

I am using below SMTP code to send emails:

        string _mailFrom = ConfigurationManager.AppSettings["mailfrom"].ToString();
        string _emailTo = ConfigurationManager.AppSettings["ScheduledServiceRecipientTO"].ToString();
        string _emailCC = ConfigurationManager.AppSettings["ScheduledServiceRecipientCC"].ToString();

        var _mailMessage = new System.Net.Mail.MailMessage();
        _mailMessage.To.Add(_emailTo);
        _mailMessage.CC.Add(new MailAddress(_emailCC));
        _mailMessage.From = new MailAddress(_mailFrom);
        _mailMessage.Subject = subject;
        _mailMessage.Body = pBody;
        _mailMessage.IsBodyHtml = true;

        try
        {
            var smtp = new System.Net.Mail.SmtpClient();
            {
                smtp.Host = ConfigurationManager.AppSettings["Host"];
                smtp.Port = Convert.ToInt32(ConfigurationManager.AppSettings["Port"]);
                //smtp.Credentials = new NetworkCredential(ConfigurationManager.AppSettings["UserName"], ConfigurationManager.AppSettings["Password"]);
            }

            smtp.Send(_mailMessage);
            return true;
        }

        catch (Exception ex)
        {
            throw new Exception(ex.Message);
        }

Please help me in solving this issue.

Thanks in advance.

Answer 1

You have to render your HTML. We do this with a RazorHelper Function and a Partial View to style your email. There is this function in a Helper Class:

public static string RenderPartialViewToString(Controller controller, string viewName, object model)
{
    controller.ViewData.Model = model;
    using (var sw = new StringWriter())
    {
        ViewEngineResult viewResult = ViewEngines.Engines.FindPartialView(controller.ControllerContext, viewName);
        var viewContext = new ViewContext(controller.ControllerContext, viewResult.View, controller.ViewData, controller.TempData, sw);
        viewResult.View.Render(viewContext, sw);

        return sw.GetStringBuilder().ToString();
    }
}

Then call it in a Controller context:

email.Body = RazorHelper.RenderPartialViewToString(this, "PartialViewName", model);