Hwnd.cs

using System;
using System.Runtime.InteropServices;
using Microsoft.UI.Xaml;
using Microsoft.UI.Xaml.Media;
using Projzo.Model;
using Windows.Foundation;

namespace Projzo.Interop
{

    public enum ShowWindowCommands : int
    {
        SW_HIDE = 0,
        SW_SHOWNORMAL = 1,
        SW_NORMAL = 1,
        SW_SHOWMINIMIZED = 2,
        SW_SHOWMAXIMIZED = 3,
        SW_MAXIMIZE = 3,
        SW_SHOWNOACTIVATE = 4,
        SW_SHOW = 5,
        SW_MINIMIZE = 6,
        SW_SHOWMINNOACTIVE = 7,
        SW_SHOWNA = 8,
        SW_RESTORE = 9,
        SW_SHOWDEFAULT = 10,
        SW_FORCEMINIMIZE = 11,
        SW_MAX = 11
    }


    public enum WindowMessage : uint
    {
        WM_USER = 0x400,
        WM_CTLCOLORSTATIC = 0x0138,
        WM_SYSCOMMAND = 0x0112,
        WM_MOVE = 0x0003,
        WM_SIZE = 0x0005
    }

    public class Hwnd
    {

        private static WndProcDelegate _currDelegate;

        [DllImport("Kernel32.dll")]
        public static extern uint GetLastError();


        [DllImport("User32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
        public static extern IntPtr FindWindowEx(IntPtr hwndParent, IntPtr hwndChildAfter, string lpszClass, string lpszWindow);

        [DllImport("User32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
        public static extern bool GetWindowRect(IntPtr hWnd, out RECT lpRect);

        [DllImport("User32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
        public static extern bool GetClientRect(IntPtr hWnd, out RECT lpRect);

        [DllImport("User32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
        public static extern bool SetWindowPos(IntPtr hWnd, IntPtr hWndInsertAfter, int X, int Y, int cx, int cy, uint uFlags);

        public const int SWP_NOSIZE = 0x0001;
        public const int SWP_NOMOVE = 0x0002;
        public const int SWP_NOZORDER = 0x0004;
        public const int SWP_NOREDRAW = 0x0008;
        public const int SWP_NOACTIVATE = 0x0010;
        public const int SWP_FRAMECHANGED = 0x0020;  /* The frame changed: send WM_NCCALCSIZE */
        public const int SWP_SHOWWINDOW = 0x0040;
        public const int SWP_HIDEWINDOW = 0x0080;
        public const int SWP_NOCOPYBITS = 0x0100;
        public const int SWP_NOOWNERZORDER = 0x0200;  /* Don't do owner Z ordering */
        public const int SWP_NOSENDCHANGING = 0x0400;  /* Don't send WM_WINDOWPOSCHANGING */
        public const int SWP_DRAWFRAME = SWP_FRAMECHANGED;
        public const int SWP_NOREPOSITION = SWP_NOOWNERZORDER;
        public const int SWP_DEFERERASE = 0x2000;
        public const int SWP_ASYNCWINDOWPOS = 0x4000;


        public static readonly IntPtr HWND_BOTTOM = (IntPtr)1;
        public static readonly IntPtr HWND_NOTOPMOST = (IntPtr)(-2);
        public static readonly IntPtr HWND_TOP = IntPtr.Zero;
        public static readonly IntPtr HWND_TOPMOST = (IntPtr)(-1);



        [DllImport("User32.dll", SetLastError = true)]
        public static extern UInt16 RegisterClassW([In] ref WNDCLASS lpWndClass);

        [DllImport("User32.dll", SetLastError = true)]
        public static extern IntPtr CreateWindowExW(int dwExStyle,
            [MarshalAs(UnmanagedType.LPWStr)]
            string lpClassName,
            [MarshalAs(UnmanagedType.LPWStr)]
            string lpWindowName, 
            int dwStyle, int x, int y, int nWidth, int nHeight, IntPtr hWndParent, IntPtr hMenu, IntPtr hInstance, IntPtr lpParam);

        public const int CS_VREDRAW = 0x0001,
            CS_HREDRAW = 0x0002;

        public const int WS_OVERLAPPED = 0x00000000,
            WS_POPUP = unchecked((int)0x80000000),
            WS_CHILD = 0x40000000,
            WS_MINIMIZE = 0x20000000,
            WS_VISIBLE = 0x10000000,
            WS_DISABLED = 0x08000000,
            WS_CLIPSIBLINGS = 0x04000000,
            WS_CLIPCHILDREN = 0x02000000,
            WS_MAXIMIZE = 0x01000000,
            WS_CAPTION = 0x00C00000,
            WS_BORDER = 0x00800000,
            WS_DLGFRAME = 0x00400000,
            WS_VSCROLL = 0x00200000,
            WS_HSCROLL = 0x00100000,
            WS_SYSMENU = 0x00080000,
            WS_THICKFRAME = 0x00040000,
            WS_TABSTOP = 0x00010000,
            WS_MINIMIZEBOX = 0x00020000,
            WS_MAXIMIZEBOX = 0x00010000,
            WS_OVERLAPPEDWINDOW = WS_OVERLAPPED |
                             WS_CAPTION |
                             WS_SYSMENU |
                             WS_THICKFRAME |
                             WS_MINIMIZEBOX |
                             WS_MAXIMIZEBOX;

        public const int WS_EX_DLGMODALFRAME = 0x00000001;
        public const int WS_EX_NOPARENTNOTIFY = 0x00000004;
        public const int WS_EX_TOPMOST = 0x00000008;
        public const int WS_EX_ACCEPTFILES = 0x00000010;
        public const int WS_EX_TRANSPARENT = 0x00000020;
        public const int WS_EX_MDICHILD = 0x00000040;
        public const int WS_EX_TOOLWINDOW = 0x00000080;
        public const int WS_EX_WINDOWEDGE = 0x00000100;
        public const int WS_EX_CLIENTEDGE = 0x00000200;
        public const int WS_EX_CONTEXTHELP = 0x00000400;
        public const int WS_EX_RIGHT = 0x00001000;
        public const int WS_EX_LEFT = 0x00000000;
        public const int WS_EX_RTLREADING = 0x00002000;
        public const int WS_EX_LTRREADING = 0x00000000;
        public const int WS_EX_LEFTSCROLLBAR = 0x00004000;
        public const int WS_EX_RIGHTSCROLLBAR = 0x00000000;
        public const int WS_EX_CONTROLPARENT = 0x00010000;
        public const int WS_EX_STATICEDGE = 0x00020000;
        public const int WS_EX_APPWINDOW = 0x00040000;
        public const int WS_EX_OVERLAPPEDWINDOW = (WS_EX_WINDOWEDGE | WS_EX_CLIENTEDGE);
        public const int WS_EX_PALETTEWINDOW = (WS_EX_WINDOWEDGE | WS_EX_TOOLWINDOW | WS_EX_TOPMOST);
        public const int WS_EX_LAYERED = 0x00080000;
        public const int WS_EX_NOINHERITLAYOUT = 0x00100000; // Disable inheritence of mirroring by children
        public const int WS_EX_NOREDIRECTIONBITMAP = 0x00200000;
        public const int WS_EX_LAYOUTRTL = 0x00400000; // Right to left mirroring
        public const int WS_EX_COMPOSITED = 0x02000000;
        public const int WS_EX_NOACTIVATE = 0x08000000;

        [DllImport("User32.dll", SetLastError = true, CharSet = CharSet.Auto)]
        public static extern bool MoveWindow(IntPtr hWnd, int x, int y, int cx, int cy, bool repaint);

        [DllImport("User32.dll", SetLastError = true, CharSet = CharSet.Auto)]
        public static extern bool ShowWindow(IntPtr hWnd, int nShowCmd);



        public const uint LWA_COLORKEY = 0x00000001;
        public const uint LWA_ALPHA = 0x00000002;

        [DllImport("User32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
        public static extern bool SetLayeredWindowAttributes(IntPtr hwnd, uint crKey, byte bAlpha, uint dwFlags);

        [DllImport("User32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
        public static extern IntPtr SetParent(IntPtr hWndChild, IntPtr hWndParent);

        const int GWL_STYLE = (-16);
        const int GWL_EXSTYLE = (-20);
        public const int GWL_WNDPROC = (-4);
        public static IntPtr SetWindowLong(IntPtr hWnd, int nIndex, IntPtr dwNewLong)
        {
            if (IntPtr.Size == 4)
            {
                return SetWindowLongPtr32(hWnd, nIndex, dwNewLong);
            }
            return SetWindowLongPtr64(hWnd, nIndex, dwNewLong);
        }

        [DllImport("User32.dll", CharSet = CharSet.Auto, EntryPoint = "SetWindowLong")]
        public static extern IntPtr SetWindowLongPtr32(IntPtr hWnd, int nIndex, IntPtr dwNewLong);

        [DllImport("User32.dll", CharSet = CharSet.Auto, EntryPoint = "SetWindowLongPtr")]
        public static extern IntPtr SetWindowLongPtr64(IntPtr hWnd, int nIndex, IntPtr dwNewLong);

        public static IntPtr SetClassLong(HandleRef hWnd, int nIndex, IntPtr dwNewLong)
        {
            if (IntPtr.Size > 4)
                return SetClassLongPtr64(hWnd, nIndex, dwNewLong);
            else
                return new IntPtr(SetClassLongPtr32(hWnd, nIndex, unchecked((uint)dwNewLong.ToInt32())));
        }

        [DllImport("user32.dll", EntryPoint = "SetClassLong")]
        public static extern uint SetClassLongPtr32(HandleRef hWnd, int nIndex, uint dwNewLong);

        [DllImport("user32.dll", EntryPoint = "SetClassLongPtr")]
        public static extern IntPtr SetClassLongPtr64(HandleRef hWnd, int nIndex, IntPtr dwNewLong);


        // public static IntPtr GetWindowLong(HandleRef hWnd, int nIndex)
        public static long GetWindowLong(IntPtr hWnd, int nIndex)
        {
            if (IntPtr.Size == 4)
            {
                return GetWindowLong32(hWnd, nIndex);
            }
            return GetWindowLongPtr64(hWnd, nIndex);
        }

        [DllImport("User32.dll", EntryPoint = "GetWindowLong", CharSet = CharSet.Auto)]
        public static extern long GetWindowLong32(IntPtr hWnd, int nIndex);

        [DllImport("User32.dll", EntryPoint = "GetWindowLongPtr", CharSet = CharSet.Auto)]
        public static extern long GetWindowLongPtr64(IntPtr hWnd, int nIndex);

        [DllImport("user32.dll")]
        public static extern IntPtr DefWindowProc(IntPtr hWnd, uint uMsg, IntPtr wParam, IntPtr lParam);

        [DllImport("user32.dll", CharSet = CharSet.Auto)]
        public static extern IntPtr CallWindowProc(IntPtr lpPrevWndFunc, IntPtr hwnd, uint msg, IntPtr wParam, IntPtr lParam);

        private const int GWLP_WNDPROC = -4;
        public delegate IntPtr WndProcDelegate(IntPtr hwnd, uint message, IntPtr wParam, IntPtr lParam);



        public static IntPtr SetWndProc(IntPtr hwnd, WndProcDelegate newProc)
        {

            //we assign to static variable so that garbage collector won't remove this instance of newProc 
            //Reference: https://www.travelneil.com/wndproc-in-uwp.html
            _currDelegate = newProc;

            IntPtr functionPointer = Marshal.GetFunctionPointerForDelegate(newProc);

            return SetWindowLong(hwnd, GWLP_WNDPROC, functionPointer);

        }

        public static IntPtr SetWndProc(Window window, WndProcDelegate newProc)
        {

            //we assign to static variable so that garbage collector won't remove this instance of newProc 
            //Reference: https://www.travelneil.com/wndproc-in-uwp.html
            _currDelegate = newProc;

            IntPtr hwnd = WinRT.Interop.WindowNative.GetWindowHandle(window);
            IntPtr functionPointer = Marshal.GetFunctionPointerForDelegate(newProc);

            return SetWindowLong(hwnd, GWLP_WNDPROC, functionPointer);

        }

        public static IntPtr SetWndProc(Window window, IntPtr newProc)
        {
            _currDelegate = null;

            IntPtr hwnd = WinRT.Interop.WindowNative.GetWindowHandle(window);
      
            return SetWindowLong(hwnd, GWLP_WNDPROC, newProc);

        }



        [DllImport("User32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
        public static extern bool GetCursorPos(out POINT point);


        public static Point GetCursorPosByWindow(IntPtr hWnd)
        {
            POINT cursorPos;
            Hwnd.GetCursorPos(out cursorPos);
            Hwnd.ScreenToClient(hWnd, ref cursorPos);
            Point pt = Dpi.UnscalePoint(new Windows.Foundation.Point(cursorPos.x, cursorPos.y));

            return pt;
        }


        //hWndBase - The main window containing this element
        public static Point GetCursorPosByFrameworkElement(FrameworkElement element, IntPtr hWndBase)
        {
            if (hWndBase == IntPtr.Zero) return new Point(0, 0);

            Point wndPt = GetCursorPosByWindow(hWndBase);

            GeneralTransform transform = element.TransformToVisual(null);

            Rect rect = transform.TransformBounds(new Rect(0, 0, element.ActualWidth, element.ActualHeight));
                        
            return new Point(wndPt.X - rect.Left, wndPt.Y - rect.Top);

        }


        [DllImport("User32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
        public static extern bool ScreenToClient(IntPtr hwnd, ref POINT point);


        public const int CCHILDREN_TITLEBAR = 5;

        [DllImport("User32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
        public static extern bool GetTitleBarInfo(IntPtr hwnd, ref TITLEBARINFO ti);


        [DllImport("user32.dll", EntryPoint = "SendMessage", CharSet = CharSet.Auto)]
        public static extern IntPtr SendMessageCopyData(IntPtr hWnd, uint Msg, IntPtr wParam, ref COPYDATASTRUCT cds);

        [return: MarshalAs(UnmanagedType.Bool)]
        [DllImport("user32.dll", SetLastError = true, CharSet = CharSet.Auto)]
        public static extern bool PostMessage(IntPtr hWnd, uint Msg, IntPtr wParam, IntPtr lParam);

        [DllImport("user32.dll")]
        [return: MarshalAs(UnmanagedType.Bool)]
        public static extern bool IsWindow(IntPtr hWnd);

        [DllImport("user32.dll")]
        [return: MarshalAs(UnmanagedType.Bool)]
        public static extern bool IsWindowVisible(IntPtr hWnd);

        [DllImport("user32.dll")]
        [return: MarshalAs(UnmanagedType.Bool)]
        public static extern bool IsZoomed(IntPtr hWnd);

        public const int SC_MINIMIZE = 0xF020;
        public const int SC_MAXIMIZE = 0xF030;
    }


    [StructLayout(LayoutKind.Sequential)]
    public struct TITLEBARINFO
    {
        public uint cbSize;
        public RECT rcTitleBar;

        [MarshalAs(UnmanagedType.ByValArray, SizeConst = Hwnd.CCHILDREN_TITLEBAR + 1)]
        public uint[] rgState;
    }


    [StructLayout(LayoutKind.Sequential)]
    public struct RECT
    {
        public int left;
        public int top;
        public int right;
        public int bottom;
        public RECT(int Left, int Top, int Right, int Bottom)
        {
            left = Left;
            top = Top;
            right = Right;
            bottom = Bottom;
        }
    }


    // Defines the x- and y-coordinates of a point
    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
    public struct POINT
    {
        public POINT(int x, int y)
        {
            this.x = x;
            this.y = y;
        }

        public int x;
        public int y;
    }


    [StructLayout(LayoutKind.Sequential)]
    public struct SIZE
    {
        private int width;
        private int height;

        public int Width { set { width = value; } }
        public int Height { set { height = value; } }
    };


    //
    // Summary:
    //     Contains message information from a thread's message queue.
    [StructLayout(LayoutKind.Sequential)]
    public struct MSG
    {
        public IntPtr hwnd;
        public int message;
        public IntPtr wParam;
        public IntPtr lParam;
        public int time;
        public int pt_x;
        public int pt_y;
    }


    [StructLayout(LayoutKind.Sequential)]
    public struct WNDCLASS
    {
        public uint style;
        public IntPtr lpfnWndProc;
        public int cbClsExtra;
        public int cbWndExtra;
        public IntPtr hInstance;
        public IntPtr hIcon;
        public IntPtr hCursor;
        public IntPtr hbrBackground;
        [MarshalAs(UnmanagedType.LPWStr)]
        public string lpszMenuName;
        [MarshalAs(UnmanagedType.LPWStr)]
        public string lpszClassName;
    }


    // Window message flags
    [Flags]
    public enum WM : uint
    {
        ACTIVATE = 0x6,
        ACTIVATEAPP = 0x1C,
        AFXFIRST = 0x360,
        AFXLAST = 0x37F,
        APP = 0x8000,
        ASKCBFORMATNAME = 0x30C,
        CANCELJOURNAL = 0x4B,
        CANCELMODE = 0x1F,
        CAPTURECHANGED = 0x215,
        CHANGECBCHAIN = 0x30D,
        CHAR = 0x102,
        CHARTOITEM = 0x2F,
        CHILDACTIVATE = 0x22,
        CLEAR = 0x303,
        CLOSE = 0x10,
        COMMAND = 0x111,
        COMPACTING = 0x41,
        COMPAREITEM = 0x39,
        CONTEXTMENU = 0x7B,
        COPY = 0x301,
        COPYDATA = 0x4A,
        CREATE = 0x1,
        CTLCOLORBTN = 0x135,
        CTLCOLORDLG = 0x136,
        CTLCOLOREDIT = 0x133,
        CTLCOLORLISTBOX = 0x134,
        CTLCOLORMSGBOX = 0x132,
        CTLCOLORSCROLLBAR = 0x137,
        CTLCOLORSTATIC = 0x138,
        CUT = 0x300,
        DEADCHAR = 0x103,
        DELETEITEM = 0x2D,
        DESTROY = 0x2,
        DESTROYCLIPBOARD = 0x307,
        DEVICECHANGE = 0x219,
        DEVMODECHANGE = 0x1B,
        DISPLAYCHANGE = 0x7E,
        DRAWCLIPBOARD = 0x308,
        DRAWITEM = 0x2B,
        DROPFILES = 0x233,
        ENABLE = 0xA,
        ENDSESSION = 0x16,
        ENTERIDLE = 0x121,
        ENTERMENULOOP = 0x211,
        ENTERSIZEMOVE = 0x231,
        ERASEBKGND = 0x14,
        EXITMENULOOP = 0x212,
        EXITSIZEMOVE = 0x232,
        FONTCHANGE = 0x1D,
        GETDLGCODE = 0x87,
        GETFONT = 0x31,
        GETHOTKEY = 0x33,
        GETICON = 0x7F,
        GETMINMAXINFO = 0x24,
        GETOBJECT = 0x3D,
        GETSYSMENU = 0x313,
        GETTEXT = 0xD,
        GETTEXTLENGTH = 0xE,
        HANDHELDFIRST = 0x358,
        HANDHELDLAST = 0x35F,
        HELP = 0x53,
        HOTKEY = 0x312,
        HSCROLL = 0x114,
        HSCROLLCLIPBOARD = 0x30E,
        ICONERASEBKGND = 0x27,
        IME_CHAR = 0x286,
        IME_COMPOSITION = 0x10F,
        IME_COMPOSITIONFULL = 0x284,
        IME_CONTROL = 0x283,
        IME_ENDCOMPOSITION = 0x10E,
        IME_KEYDOWN = 0x290,
        IME_KEYLAST = 0x10F,
        IME_KEYUP = 0x291,
        IME_NOTIFY = 0x282,
        IME_REQUEST = 0x288,
        IME_SELECT = 0x285,
        IME_SETCONTEXT = 0x281,
        IME_STARTCOMPOSITION = 0x10D,
        INITDIALOG = 0x110,
        INITMENU = 0x116,
        INITMENUPOPUP = 0x117,
        INPUTLANGCHANGE = 0x51,
        INPUTLANGCHANGEREQUEST = 0x50,
        KEYDOWN = 0x100,
        KEYFIRST = 0x100,
        KEYLAST = 0x108,
        KEYUP = 0x101,
        KILLFOCUS = 0x8,
        LBUTTONDBLCLK = 0x203,
        LBUTTONDOWN = 0x201,
        LBUTTONUP = 0x202,
        LVM_GETEDITCONTROL = 0x1018,
        LVM_SETIMAGELIST = 0x1003,
        MBUTTONDBLCLK = 0x209,
        MBUTTONDOWN = 0x207,
        MBUTTONUP = 0x208,
        MDIACTIVATE = 0x222,
        MDICASCADE = 0x227,
        MDICREATE = 0x220,
        MDIDESTROY = 0x221,
        MDIGETACTIVE = 0x229,
        MDIICONARRANGE = 0x228,
        MDIMAXIMIZE = 0x225,
        MDINEXT = 0x224,
        MDIREFRESHMENU = 0x234,
        MDIRESTORE = 0x223,
        MDISETMENU = 0x230,
        MDITILE = 0x226,
        MEASUREITEM = 0x2C,
        MENUCHAR = 0x120,
        MENUCOMMAND = 0x126,
        MENUDRAG = 0x123,
        MENUGETOBJECT = 0x124,
        MENURBUTTONUP = 0x122,
        MENUSELECT = 0x11F,
        MOUSEACTIVATE = 0x21,
        MOUSEFIRST = 0x200,
        MOUSEHOVER = 0x2A1,
        MOUSELAST = 0x20A,
        MOUSELEAVE = 0x2A3,
        MOUSEMOVE = 0x200,
        MOUSEWHEEL = 0x20A,
        MOVE = 0x3,
        MOVING = 0x216,
        NCACTIVATE = 0x86,
        NCCALCSIZE = 0x83,
        NCCREATE = 0x81,
        NCDESTROY = 0x82,
        NCHITTEST = 0x84,
        NCLBUTTONDBLCLK = 0xA3,
        NCLBUTTONDOWN = 0xA1,
        NCLBUTTONUP = 0xA2,
        NCMBUTTONDBLCLK = 0xA9,
        NCMBUTTONDOWN = 0xA7,
        NCMBUTTONUP = 0xA8,
        NCMOUSEHOVER = 0x2A0,
        NCMOUSELEAVE = 0x2A2,
        NCMOUSEMOVE = 0xA0,
        NCPAINT = 0x85,
        NCRBUTTONDBLCLK = 0xA6,
        NCRBUTTONDOWN = 0xA4,
        NCRBUTTONUP = 0xA5,
        NEXTDLGCTL = 0x28,
        NEXTMENU = 0x213,
        NOTIFY = 0x4E,
        NOTIFYFORMAT = 0x55,
        NULL = 0x0,
        PAINT = 0xF,
        PAINTCLIPBOARD = 0x309,
        PAINTICON = 0x26,
        PALETTECHANGED = 0x311,
        PALETTEISCHANGING = 0x310,
        PARENTNOTIFY = 0x210,
        PASTE = 0x302,
        PENWINFIRST = 0x380,
        PENWINLAST = 0x38F,
        POWER = 0x48,
        PRINT = 0x317,
        PRINTCLIENT = 0x318,
        QUERYDRAGICON = 0x37,
        QUERYENDSESSION = 0x11,
        QUERYNEWPALETTE = 0x30F,
        QUERYOPEN = 0x13,
        QUEUESYNC = 0x23,
        QUIT = 0x12,
        RBUTTONDBLCLK = 0x206,
        RBUTTONDOWN = 0x204,
        RBUTTONUP = 0x205,
        RENDERALLFORMATS = 0x306,
        RENDERFORMAT = 0x305,
        SETCURSOR = 0x20,
        SETFOCUS = 0x7,
        SETFONT = 0x30,
        SETHOTKEY = 0x32,
        SETICON = 0x80,
        SETMARGINS = 0xD3,
        SETREDRAW = 0xB,
        SETTEXT = 0xC,
        SETTINGCHANGE = 0x1A,
        SHOWWINDOW = 0x18,
        SIZE = 0x5,
        SIZECLIPBOARD = 0x30B,
        SIZING = 0x214,
        SPOOLERSTATUS = 0x2A,
        STYLECHANGED = 0x7D,
        STYLECHANGING = 0x7C,
        SYNCPAINT = 0x88,
        SYSCHAR = 0x106,
        SYSCOLORCHANGE = 0x15,
        SYSCOMMAND = 0x112,
        SYSDEADCHAR = 0x107,
        SYSKEYDOWN = 0x104,
        SYSKEYUP = 0x105,
        TCARD = 0x52,
        TIMECHANGE = 0x1E,
        TIMER = 0x113,
        TVM_GETEDITCONTROL = 0x110F,
        TVM_SETIMAGELIST = 0x1109,
        UNDO = 0x304,
        UNINITMENUPOPUP = 0x125,
        USER = 0x400,
        USERCHANGED = 0x54,
        VKEYTOITEM = 0x2E,
        VSCROLL = 0x115,
        VSCROLLCLIPBOARD = 0x30A,
        WINDOWPOSCHANGED = 0x47,
        WINDOWPOSCHANGING = 0x46,
        WININICHANGE = 0x1A,
        SH_NOTIFY = 0x0401
    }


    [StructLayout(LayoutKind.Sequential)]
    public struct COPYDATASTRUCT
    {
        public IntPtr dwData;    // Any value the sender chooses.  Perhaps its main window handle?
        public int cbData;       // The count of bytes in the message.

        [MarshalAs(UnmanagedType.LPWStr)]
        public string lpData;    
    }

}