css 样式在 javax 邮件中不起作用 api

Question

当我收到 JavaMail api 发送的电子邮件时，css 不起作用，只呈现 html。

HTML 代码

        <!doctype html>
    <html lang="en">
    <head>
      <meta charset="utf-8">
      <meta name="viewport" content="width=device-width, initial-scale=1">
      <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">

      <title>title</title>

      <style>

        .gradiente{
          background: -webkit-linear-gradient(#FFFCE8, #FFF8AF); /* For Safari 5.1 to 6.0 */
          background: -o-linear-gradient(#FFFCE8, #FFF8AF); /* For Opera 11.1 to 12.0 */
          background: -moz-linear-gradient(#FFFCE8, #FFF8AF); /* For Firefox 3.6 to 15 */
          background: linear-gradient(#FFFCE8, #FFF8AF); /* Standard syntax */
          background-repeat: repeat;

        }  
        a lot of styles below....... I did not paste all of it
    </style>
</head>
    <body class='gradiente'>
      ....html stuff
    </body>
</html>

JAVA API

// Get system properties
          Properties properties = System.getProperties();

          // Setup mail server
          properties.setProperty("mail.smtp.auth", "true");
          properties.setProperty("mail.smtp.starttls.enable", "true");
          properties.setProperty("mail.smtp.host", host);
          properties.setProperty("mail.smtp.port", porta);

          MailcapCommandMap mc = (MailcapCommandMap)CommandMap.getDefaultCommandMap();  
            mc.addMailcap("text/html;; x-java-content-handler=com.sun.mail.handlers.text_html"); 
            mc.addMailcap("text/css;; x-java-content-handler=com.sun.mail.handlers.text_css");  
            mc.addMailcap("text/xml;; x-java-content-handler=com.sun.mail.handlers.text_xml");  
            mc.addMailcap("text/plain;; x-java-content-handler=com.sun.mail.handlers.text_plain");  
            mc.addMailcap("multipart/*;; x-java-content-handler=com.sun.mail.handlers.multipart_mixed");  
            mc.addMailcap("message/rfc822;; x-java-content-handler=com.sun.mail.handlers.message_rfc822");  
            CommandMap.setDefaultCommandMap(mc); 

          Session session = Session.getInstance(properties,
                  new javax.mail.Authenticator() {
                    protected PasswordAuthentication getPasswordAuthentication() {
                        return new PasswordAuthentication(userName, passWord);
                    }
                  });

          try{
            // Create a default MimeMessage object.
              MimeMessage message = new MimeMessage(session);

              // Set From: header field of the header.
              message.setFrom(new InternetAddress(from));

              // Set To: header field of the header.
              message.addRecipient(Message.RecipientType.TO,
                                       new InternetAddress(to));

             if(cc != null){
                  Iterator<String> ccIt = cc.iterator();
                  while (ccIt.hasNext()) {
                    String itemcc = ccIt.next();
                    message.addRecipient(Message.RecipientType.CC,
                            new InternetAddress(itemcc));
                  }
             }

               // Create the message part 
               BodyPart messageBodyPart = new MimeBodyPart();

              // Set Subject: header field
              message.setSubject(subject);

              // Send the actual HTML message, as big as you like
              Iterator<String> it = content.iterator();
              String textoConteudo="";
              while (it.hasNext()) {
                String item = it.next();
                textoConteudo = textoConteudo + item;
              }
              messageBodyPart.setContent(textoConteudo,
                                 "text/html; charset=iso-8859-1" );

           // Create a multipar message
              Multipart multipart = new MimeMultipart();

           // Set text message part
              multipart.addBodyPart(messageBodyPart);

             // Part two is attachment
              if(fileName !=null){
                  Iterator<String> itFN = fileName.iterator();
                  while (itFN.hasNext()) {
                     String arq = itFN.next();
                     messageBodyPart = new MimeBodyPart();
                     DataSource source = new FileDataSource(arq);
                     messageBodyPart.setDataHandler(new DataHandler(source));
                     messageBodyPart.setFileName(arq);
                     multipart.addBodyPart(messageBodyPart);
                  }
              }
              // Send the complete message parts
              message.setContent(multipart );

             // Send message
             Transport.send(message);

当我收到一封新邮件并在 gmail 或 outlook 中打开它时，只呈现 html 代码。 css 样式未应用...

Answer 1

我认为java邮件中的html是从body标签开始的，无法读取css样式它必须在标签样式本身
试试这个

<html>
    <body style=" background: -webkit-linear-gradient(#FFFCE8, #FFF8AF); /* For Safari 5.1 to 6.0 */           background: -o-linear-gradient(#FFFCE8, #FFF8AF); /* For Opera 11.1 to 12.0 */           background: -moz-linear-gradient(#FFFCE8, #FFF8AF); /* For Firefox 3.6 to 15 */           background: linear-gradient(#FFFCE8, #FFF8AF); /* Standard syntax */           background-repeat: repeat;">
      ....html stuff
    </body>
</html>

Answer 2

一般来说，电子邮件客户端不会让您随意使用 CSS。 This article 将帮助您了解哪个客户端支持什么。

css 样式在 javax 邮件中不起作用 api

css style does not work in javax mail api

html

css

java

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