using System;
[Serializable]
public sealed class MailReceivedEventArgs : EventArgs {
private readonly string from;
private readonly string subject;
public MailReceivedEventArgs(string from, string subject) {
this.from = from;
this.subject = subject;
}
public string From { get { return from; } }
public string Subject { get { return subject; } }
}
public class MainClass {
public static void Main() {
MailReceivedEventArgs args = new MailReceivedEventArgs("D", "Y");
Console.WriteLine("From: {0}, Subject: {1}", args.From, args.Subject);
}
}