如何使用 ThymeLeaf 发送带有内联图像的电子邮件

Question

我正在尝试使用 ThymeLeaf 和 Spring 发送带有内联图像的电子邮件，但到目前为止没有成功。电子邮件已发送，但内联图像不会显示在电子邮件中。

该项目不是基于网络的（不是网站），而是桌面独立的，不是移动的

这是我获取图像文件的方式：

URL url = getClass().getResource("/LawFirmAdvisoryGroup.jpg");
File file = new File(url.getPath());

MultipartFile multipartFile = new MockMultipartFile(file.getName(),
    file.getName(), "image/jpeg", IOUtils.toByteArray(input));

我的服务class:

@Autowired
private JavaMailSender mailSender;

@Autowired
private TemplateEngine templateEngine;

public void sendMailWithInline(final String recipientName, final String recipientEmail, final MultipartFile image, final byte[] imageBytes)
throws MessagingException {

    final Context ctx = new Context();
        ctx.setVariable("imageResourceName", image.getName()); // so that we can reference it from HTML

        final MimeMessage mimeMessage = this.mailSender.createMimeMessage();
        final MimeMessageHelper message
        = new MimeMessageHelper(mimeMessage, true, "UTF-8");
        message.setSubject("Inline Image");
        message.setFrom("XXXX@yahoo.com");
        message.setTo(recipientEmail);

        // Add the inline image, referenced from the HTML code as "cid:${imageResourceName}"
        final InputStreamSource imageSource = new ByteArrayResource(imageBytes);
        message.addInline(image.getName(), imageSource, image.getContentType());


        final String htmlContent = this.templateEngine.process("left_sidebar.html", ctx);
        message.setText(htmlContent, true);
        this.mailSender.send(mimeMessage);

    }

HTML:

<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org">
  <head>
    <title th:remove="all">Email with inline image</title>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
  </head>
  <body>
    <p>
      <img src="LawFirmAdvisoryGroup.jpg" th:src="'cid:' + ${imageResourceName}" />
    </p>
  </body>
</html>

Answer 1

只需将您的呼叫移至 setText() 几行。

MimeMessageHelper.addInLine() 的 javadoc 说：

NOTE: Invoke addInline after setText(java.lang.String); else, mail readers might not be able to resolve inline references correctly.

Answer 2

这非常有效：

只需将 link 添加到托管在远离您桌面的外部服务器上的图像。使用内联 CSS，而不是 CSS 类.

本网站将帮助您将 CSS 类转换为内联 CSS, Premailer.Dialect.

避免花哨CSS，只使用最基本的。如果您希望 HTML 邮件轻松流动，即使在移动设备和其他较小的屏幕中，也应尽可能避免浮动（如 float: left;）。

包括 NekoHTML in your project libraries, and change your Spring spring.xml 到：

<!-- THYMELEAF: Template Resolver for email templates -->
<bean id="emailTemplateResolver" class="org.thymeleaf.templateresolver.ClassLoaderTemplateResolver">
    <property name="prefix" value="resources/WEB_INF/HTMLMailTemplates/XXXX/html/" />
    <!-- <property name="templateMode" value="HTML5" /> -->
    <property name="templateMode" value="LEGACYHTML5" />
    <property name="characterEncoding" value="UTF-8" />
    <property name="order" value="1" />
</bean>

示例：

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title>Email With Inline Images</title>

    <style>
        body {
            background-image: url('https://dl.dropbox.com/s/XXXX/pageBackGround.gif');
            background-repeat: repeat;
            margin:0;
            outline:0;
        }
        .pageContentWrapper {
            padding:10px;
            width: 100%;
            background-image: url('https://dl.dropbox.com/s/XXXX/smallerInlineImage.gif');
            background-repeat: repeat;
        }
        .smallerInlineImage {
            width: 22px;
            height: 22px;
            padding: 0 4px 6px 0;
            float: left;
        }
    </style>

</head>

<body>
    <div class="pageContentWrapper">
        <div class="smallerInlineImage">
            <img src="https://dl.dropboxusercontent.com/s/3ydel6zp53pb65b/smallerInlineImage.png" height="22" width="22">
        </div>
    </div>
</body>

服务Class:

@Service
public class ThymeEmailService {

    @Autowired
    private JavaMailSender mailSender;

    @Autowired
    private TemplateEngine templateEngine;

    public void sendMailWithInline() throws MessagingException {

        final Context ctx = new Context();

        final MimeMessage mimeMessage = this.mailSender.createMimeMessage();
        final MimeMessageHelper message = new MimeMessageHelper(mimeMessage, true, "UTF-8");
        message.setSubject("Sample Email Subject");
        message.setFrom("senderEmail@yahoo.com");
        message.setTo("recipientEmail@yahoo.com");

        final String htmlContent = this.templateEngine.process("emailTemplate.html", ctx);
        message.setText(htmlContent, true);

        String[] attachments = {"C:\Users\MyPc\Dropbox\CV\myPDFAttachment.pdf"};

        for (String attachment : attachments) {
            FileSystemResource file = new FileSystemResource(attachment);
            message.addAttachment(file.getFilename(), file);
        }

        this.mailSender.send(mimeMessage);
    }
}

如何使用 ThymeLeaf 发送带有内联图像的电子邮件

How to send email with inline image using ThymeLeaf

java

thymeleaf