Question

试图用 GUI 做一个基本的邮件发送器应用程序，但无论我做什么都不能发送/添加多个附件（尝试了旧 Stack Overflow 问题中的大部分答案 - 没有用，
我不想手动添加“multipart.addBodyPart(messageBodyPart);”对于每个附件。有没有办法添加多个附件而无需一遍又一遍地重复代码）。我错过了什么，出了什么问题？（完整的GUI照片作为附件添加，红色字为变量名称
链接 = [1]: https://i.stack.imgur.com/KVVc9.png )

var canvas3 = document.getElementById('canvas3');
var websocket = new WebSocket("ws://127.0.0.1:9999");
var player3 = new jsmpeg(websocket, { canvas: canvas3, autoplay: true, loop: true })

Answer 1

这是一个最小的 GUI，有两个按钮，附加和发送，还有一个用于收集选定文件的文本区域，我没有复制你的完整 GUI，所以你必须将它集成到你的代码中。

实际上，您只需检查 onAttach() 选择附件和 onSend()，其中 for 循环将所有选定的附件添加到邮件中。

还要注意，textarea只用于显示选中的文件，但文件列表保存在一个ArrayList中。

import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.io.File;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;

import javax.mail.Authenticator;
import javax.mail.Message;
import javax.mail.Multipart;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeBodyPart;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;
import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;

public class TestEmail extends JPanel {

    String fromEmail = "myemail@mydomain.com";
    String toEmail = "destmail@anotherdomain.com";

    protected JButton attachButton=new JButton("Add attachment(s)");
    protected JButton sendButton=new JButton("Send");
    protected JTextArea attachmentsArea=new JTextArea(10, 30);
    protected JFileChooser chooser=new JFileChooser();
    
    protected List<File> attachments=new ArrayList<File>();

    public TestEmail() {
        setLayout(new BorderLayout());

        attachmentsArea.setEditable(false);
        chooser.setMultiSelectionEnabled(true);

        JScrollPane scrollPane=new JScrollPane(attachmentsArea);
        add(scrollPane,BorderLayout.CENTER);
        
        Box buttonPanel=new Box(BoxLayout.X_AXIS);
        buttonPanel.add(Box.createHorizontalGlue());
        buttonPanel.add(attachButton);
        buttonPanel.add(sendButton);
        
        add(buttonPanel,BorderLayout.SOUTH);
        attachButton.addActionListener((e)->onAttach());
        sendButton.addActionListener((e)->onSend());
    }

    public Session getSession() {
        final String password = "mypassword";
        Properties props = new Properties();
        props.put("mail.smtp.host", "smtp.mydomain.com"); // SMTP Host
        props.put("mail.smtp.port", "465");
        props.put("mail.smtp.auth", "true"); // enable authentication
        props.put("mail.smtp.socketFactory.class",
                "javax.net.ssl.SSLSocketFactory");  
        Authenticator auth = new Authenticator() {
            // override the getPasswordAuthentication method
            protected PasswordAuthentication getPasswordAuthentication() {
                return new PasswordAuthentication(fromEmail, password);
            }
        };

        return Session.getInstance(props, auth);
    }

    public void onAttach() {
        if (chooser.showOpenDialog(this)==JFileChooser.APPROVE_OPTION) {
            for (File f: chooser.getSelectedFiles()) {
                if (!f.isDirectory()&&!attachments.contains(f)) {
                    attachments.add(f);
                    attachmentsArea.append(f.getAbsolutePath()+"\n");
                }
            }
        }
    }
    
    public void onSend() {
        try {
            Session session = getSession();
            Message message = new MimeMessage(session);
            message.setFrom(new InternetAddress(fromEmail));
            message.setRecipients(Message.RecipientType.TO, InternetAddress.parse(toEmail));
            message.setSubject("A subject");
    
            MimeBodyPart messageBodyPart = new MimeBodyPart();
            messageBodyPart.setText("Dummy message, just to send attachments.");
    
            Multipart multipart = new MimeMultipart();
            multipart.addBodyPart(messageBodyPart);
    
            for (File f: attachments) {
                MimeBodyPart part=new MimeBodyPart();
                part.attachFile(f);
                multipart.addBodyPart(part);
            }
            message.setContent(multipart);
            Transport.send(message);
            JOptionPane.showMessageDialog(this, "Message successfully sent", "Success", JOptionPane.INFORMATION_MESSAGE);
        } catch (Exception ex) {
            ex.printStackTrace();
            JOptionPane.showMessageDialog(this, "Exception sending e-mail:\n"+ex.getMessage(),"Error", JOptionPane.ERROR_MESSAGE);
        }
    }
    
    public static void main(String[] args) {
        EventQueue.invokeLater(()->{
            JFrame frame=new JFrame("Sendmail");
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            frame.setContentPane(new TestEmail());
            frame.pack();
            frame.setVisible(true);
        });
    }
}

带有gui的javamail多个附件

1 个答案: