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我希望发送一封带有纯文本和 html 版本的电子邮件。电子邮件需要一张图片来搭配它（不是我可以在其他地方托管的），如果客户在 html 中查看它，它应该被嵌入，并附加用于纯文本视图。

这是否可能适用于所有普通客户？

我最接近的是将图像创建为附件（而不是链接资源），然后在 html 中使用 cid:filename.jpg 引用它。但是，这在 gmail 中不起作用（它不会在 html 中显示图像）。

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2 回答 2

6

此代码片段适用于 Outlook 2010 和 gmail。我通过暂时将纯文本部分放在电子邮件的最后来测试纯文本电子邮件，这使得 gmail 使用它。

它还演示了一些其他很酷的东西，例如电子邮件模板和标签替换。


public void SendEmailWithPicture(string email, byte[] image)
{
    string filename = "AttachmentName.jpg";

    LinkedResource linkedResource = new LinkedResource(new MemoryStream(image), "image/jpg");
    linkedResource.ContentId = filename;
    linkedResource.ContentType.Name = filename;

    this.Send(
        EmailTemplates.sendpicture,
        this.Subjects.SendPicture,
        new List() { email },
        this.ReplyTo,
        tagValues: new Dictionary() { { "ImageAttachmentName", "cid:" + filename } },
        htmlLinkedResources: new List() { linkedResource }
        );
}

private void Send(EmailTemplates template, string subject, List to, string replyTo,
    Dictionary tagValues = null, List attachments = null, List htmlLinkedResources = null)
{
    try
    {
        MailMessage mailMessage = new MailMessage();

        // Set up the email header.
        to.ForEach(t => mailMessage.To.Add(new MailAddress(t)));
        mailMessage.ReplyToList.Add(new MailAddress(replyTo));
        mailMessage.Subject = subject;

        string fullTemplatePath = Path.Combine(this.TemplatePath, EMAIL_TEMPLATE_PATH);

        // Load the email bodies
        var htmlBody = File.ReadAllText(Path.Combine(fullTemplatePath, Path.ChangeExtension(template.ToString(), "html")));
        var textBody = File.ReadAllText(Path.Combine(fullTemplatePath, Path.ChangeExtension(template.ToString(), "txt")));

        // Replace the tags in the emails
        if (tagValues != null)
        {
            foreach (var entry in tagValues)
            {
                string tag = "{{" + entry.Key + "}}";

                htmlBody = htmlBody.Replace(tag, entry.Value);
                textBody = textBody.Replace(tag, entry.Value);
            }
        }

        // Create plain text alternative view
        string baseTxtTemplate = File.ReadAllText(Path.Combine(fullTemplatePath, TXT_BASE_TEMPLATE));
        textBody = baseTxtTemplate.Replace(TAG_CONTENT, textBody);
        AlternateView textView = AlternateView.CreateAlternateViewFromString(textBody, new System.Net.Mime.ContentType("text/plain"));

        // Create html alternative view
        string baseHtmlTemplate = File.ReadAllText(Path.Combine(fullTemplatePath, HTML_BASE_TEMPLATE));
        htmlBody = baseHtmlTemplate.Replace(TAG_CONTENT, htmlBody);
        AlternateView htmlView = AlternateView.CreateAlternateViewFromString(htmlBody, new System.Net.Mime.ContentType("text/html"));
        // Add any html linked resources
        if (htmlLinkedResources != null)
        {
            htmlLinkedResources.ForEach(lr => htmlView.LinkedResources.Add(lr));
            htmlLinkedResources.ForEach(lr => textView.LinkedResources.Add(lr));
        }

        // Add the two views (gmail will always display plain text version if its added last)
        mailMessage.AlternateViews.Add(textView);
        mailMessage.AlternateViews.Add(htmlView);

        // Add any attachments
        if (attachments != null)
        {
            attachments.ForEach(a => mailMessage.Attachments.Add(a));
        }

        // Send the email.
        SmtpClient smtp = new SmtpClient();
        smtp.Send(mailMessage);
    }
    catch (Exception ex)
    {
        throw new Exception(String.Format("Error sending email (to:{0}, replyto:{1})", String.Join(",", to), replyTo), ex);
    }
}
于 2011-07-05T09:03:13.330 回答
1

纯文本视图，正是如此。它是纯文本，没有可见的图像。您可以附上图片，但不能让他们查看。

查看 Outlook 发送的原始电子邮件，例如如何显示内联附件。作为一个例子，这里有一些其他人做的代码：http ://blog.devexperience.net/en/12/Send_an_Email_in_CSharp_with_Inline_attachments.aspx

-- 显然上面的链接不再有效 - 一个快速的谷歌提供了以下示例来内联图片

string htmlBody = "<html><body><h1>Picture</h1><br><img src=\"cid:Pic1\"></body></html>";
AlternateView avHtml = AlternateView.CreateAlternateViewFromString
    (htmlBody, null, MediaTypeNames.Text.Html);

// Create a LinkedResource object for each embedded image
LinkedResource pic1 = new LinkedResource("pic.jpg", MediaTypeNames.Image.Jpeg);
pic1.ContentId = "Pic1";
avHtml.LinkedResources.Add(pic1);


// Add the alternate views instead of using MailMessage.Body
MailMessage m = new MailMessage();
m.AlternateViews.Add(avHtml);

// Address and send the message
m.From = new MailAddress("email1@host.com", "From guy");
m.To.Add(new MailAddress("email2@host.com", "To guy"));
m.Subject = "A picture using alternate views";
SmtpClient client = new SmtpClient("mysmtphost.com");
client.Send(m);
于 2011-07-04T16:34:25.520 回答