使用日历取消会议请求

您可以使用 Aspose.Email 的 Appointment 类对象发送会议取消请求。需要拥有原始会议请求信息才能取消请求。本文示例首先发送会议请求，将信息保存到数据库，然后基于消息 ID 取消请求。

发送会议请求

在我们能够之前 取消会议请求，我们必须发送一些。

1. 首先创建 SmtpClient 类型的实例用于发送消息。
2. 将所有参会者信息保存到 MailAddressCollection 集合中。
3. 创建 MailMessage 类的实例并设置必要属性，如 From、To 和 Subject。
4. 创建 Appointment 类型的实例，并提供地点、开始时间、结束时间、组织者和参会者信息。
5. 将所有信息保存到数据库中。与数据库相关的工作在 SaveIntoDB 方法中完成。

以下代码片段演示了如何发送会议请求。

class Attendees {
    public String MessageId;
    public String EmailAddress;
    public String DisplayName;
}

class Message {
    public String MessageId;
    public String From;
    public String Subject;
    public String Body;
    public String AppLocation;
    public Date AppStartDate;
    public Date AppEndDate;
    public String AppSummary;
    public String AppDescription;
}

public void send(Attendees[] attendeesArr, String from, String appLocation, Date appStartDate, Date appEndDate) {
    try {
        // Create an instance of SMTPClient
        SmtpClient client = new SmtpClient("MailServer", "Username", "Password");
        // Get the attendees
        MailAddressCollection attendees = new MailAddressCollection();
        for (Attendees a : attendeesArr) {
            attendees.addItem(new MailAddress(a.EmailAddress, a.DisplayName));
        }

        // Create an instance of MailMessage for sending the invitation
        MailMessage msg = new MailMessage();

        // Set from address, attendees
        msg.setFrom(new MailAddress(from));
        msg.setTo(attendees);

        // Create am instance of Appointment
        Appointment app = new Appointment(appLocation, appStartDate, appEndDate, new MailAddress(from), attendees);
        app.setSummary("Monthly Meeting");
        app.setDescription("Please confirm your availability.");
        msg.addAlternateView(app.requestApointment());

        // Save the info to the database
        if (saveIntoDB(msg, app) == true) {
            // Save the message and Send the message with the meeting request
            msg.save(msg.getMessageId() + ".eml", SaveOptions.getDefaultEml());
            client.send(msg);
            System.out.println("message sent");
        }
    } catch (Exception ex) {
        System.err.println(ex);
    }
}

private boolean saveIntoDB(MailMessage msg, Appointment app) {
    // Save Message and Appointment information
    Message messageRow = new Message();
    messageRow.MessageId = msg.getMessageId();
    messageRow.From = msg.getFrom().getAddress();
    messageRow.Subject = msg.getSubject();
    messageRow.Body = msg.getBody();
    messageRow.AppLocation = app.getLocation();
    messageRow.AppStartDate = app.getStartDate();
    messageRow.AppEndDate = app.getEndDate();
    messageRow.AppSummary = app.getSummary();
    messageRow.AppDescription = app.getDescription();
    addToDB(messageRow);

    // Save attendee information
    for (MailAddress address : app.getAttendees()) {
        Attendees attendeesRow = new Attendees();
        attendeesRow.MessageId = msg.getMessageId();
        attendeesRow.EmailAddress = address.getAddress();
        attendeesRow.DisplayName = address.getDisplayName();
        addToDB(attendeesRow);
    }

    return true;
}

取消会议请求

要取消会议请求，首先获取邮件的消息 ID。由于我们在本示例中已将此信息保存在数据库中，因此可以轻松重新获取。

1. 选择要发送取消请求的邮件。
2. 点击 Send Cancel Request 发送请求。
3. 查询数据库以获取与参会者、消息和日历相关的信息。
4. 使用从数据库检索的信息创建 Calendar 类和 MailMessage 类的实例。
5. 使用 Appointment.cancelAppointment() 方法发送取消请求。
6. 使用 SMTP 发送邮件。

以下代码片段演示了如何取消会议请求。

public void cancel(String messageId) {
    // Get the message and calendar information from the database get the attendee information

    // Get the attendee information in reader
    Attendees[] attendeesRows = getAttendeesFromDB(messageId);

    // Create a MailAddressCollection from the attendees found in the database
    MailAddressCollection attendees = new MailAddressCollection();
    for (Attendees attendeesRow : attendeesRows) {
        attendees.addItem(new MailAddress(attendeesRow.EmailAddress, attendeesRow.DisplayName));
    }
    // Get message and calendar information
    Message messageRow = getMessageFromDB(messageId);

    // Create the Calendar object from the database information
    Appointment app = new Appointment(messageRow.AppLocation, messageRow.AppSummary, messageRow.AppDescription, messageRow.AppStartDate, messageRow.AppEndDate,
            new MailAddress(messageRow.From), attendees);

    // Create message and Set from and to addresses and Add the cancel meeting request
    MailMessage msg = new MailMessage();
    msg.setFrom(new MailAddress(messageRow.From));
    msg.setTo(attendees);
    msg.setSubject("Cencel meeting");
    msg.addAlternateView(app.cancelAppointment());
    SmtpClient smtp = new SmtpClient("smtp.gmail.com", 587, "[e-mail]", "password");
    smtp.send(msg);
    System.out.println("cancellation request successfull");
}