Skype4COM and WM_WTSESSION_CHANGE

SkypeControlForm.cs

using System;
using System.Data;
using System.Runtime.InteropServices;
using System.Windows.Forms;

namespace KrdLab.Skype
{
    // 画面ロックを検知して，Skype の UserStatus を Away/Online と切り換えるだけ．
    public partial class SkypeControlForm : Form
    {
        [DllImport("wtsapi32.dll", SetLastError = true)]
        static extern bool WTSRegisterSessionNotification(IntPtr hWnd, int dwFlags);
        [DllImport("wtsapi32.dll", SetLastError = true)]
        private static extern bool WTSUnRegisterSessionNotification(IntPtr hWnd);

        private const int WM_WTSSESSION_CHANGE = 0x02B1;
        private const int WTS_SESSION_LOCK = 0x7;
        private const int WTS_SESSION_UNLOCK = 0x8;
        private const int NOTIFY_FOR_THIS_SESSION = 0;

        private event Action<Message> WTSessionChange;

        private readonly SKYPE4COMLib.Skype skype;

        public SkypeControlForm()
        {
            InitializeComponent();

            this.HandleCreated += (s, e) =>
                WTSRegisterSessionNotification(this.Handle, NOTIFY_FOR_THIS_SESSION);
            this.HandleDestroyed += (s, e) =>
                WTSUnRegisterSessionNotification(this.Handle);

            this.Load += OnLoad;
            this.WTSessionChange += (m) =>
            {
                switch ((int)m.WParam)
                {
                    case WTS_SESSION_LOCK:
                        OnWTSessionLocked();
                        break;
                    case WTS_SESSION_UNLOCK:
                        OnWTSessionUnlocked();
                        break;
                }
            };

            this.skype = new SKYPE4COMLib.Skype();
        }

        #region Message Handler

        protected override void WndProc(ref Message m)
        {
            if (m.Msg == WM_WTSSESSION_CHANGE)
            {
                this.WTSessionChange(m);
            }
            base.WndProc(ref m);
        }

        void OnLoad(object sender, EventArgs e)
        {
            AttachSkypeClient();
            LogInfo("loaded");
        }

        void OnWTSessionLocked()
        {
            skype.ChangeUserStatus(SKYPE4COMLib.TUserStatus.cusAway);
            LogInfo("change to Away");
        }

        void OnWTSessionUnlocked()
        {
            skype.ChangeUserStatus(SKYPE4COMLib.TUserStatus.cusOnline);
            LogInfo("change to Online");
        }

        #endregion

        private void AttachSkypeClient()
        {
            if (!skype.Client.IsRunning)
            {
                skype.Client.Start(true, true);
            }
            skype.Attach(8, true);
        }

        private void LogInfo(string message)
        {
            msgBox.Items.Add(NewLoggingItem(message));
        }

        private string NewLoggingItem(string message)
        {
            return DateTime.Now + ": " + message;
        }
    }
}