How to remove the MenuBar of an application using windows API?

Question

I am using the below code to remove the Title Bar of an application, which is working perfectly for notepad. Now i want to remove the Menu Bar also. How to achieve it ?

  //Finds a window by class name
        [DllImport("USER32.DLL")]
        public static extern IntPtr FindWindow(string lpClassName, string lpWindowName);

        //Sets a window to be a child window of another window
        [DllImport("USER32.DLL")]
        public static extern IntPtr SetParent(IntPtr hWndChild, IntPtr hWndNewParent);

        //Sets window attributes
        [DllImport("USER32.DLL")]
        public static extern int SetWindowLong(IntPtr hWnd, int nIndex, int dwNewLong);

        //Gets window attributes
        [DllImport("USER32.DLL")]
        public static extern int GetWindowLong(IntPtr hWnd, int nIndex);

        [DllImport("user32.dll", EntryPoint = "FindWindow", SetLastError = true)]
        static extern IntPtr FindWindowByCaption(IntPtr ZeroOnly, string lpWindowName);


        //assorted constants needed
        public static int GWL_STYLE = -16; 
        public static int WS_BORDER = 0x00800000; //window with border
        public static int WS_DLGFRAME = 0x00400000; //window with double border but no title
        public static int WS_CAPTION = WS_BORDER | WS_DLGFRAME; //window with a title bar

        public void WindowsReStyle()
        { 
            Process[] Procs = Process.GetProcesses();
            foreach (Process proc in Procs)
            {

                if (proc.ProcessName.StartsWith("notepad"))
                {
                    IntPtr pFoundWindow = proc.MainWindowHandle;
                    int style = GetWindowLong(pFoundWindow, GWL_STYLE);
                    SetWindowLong(pFoundWindow, GWL_STYLE, (style & ~WS_CAPTION));
                }
            }
    }

Answer 1

You can't hide them, you will need to remove them using the API instead, YMMV on the result of doing this;

    [DllImport("USER32.DLL")]
    public static extern IntPtr FindWindow(string lpClassName, string lpWindowName);

    [DllImport("user32.dll", EntryPoint = "FindWindow", SetLastError = true)]
    static extern IntPtr FindWindowByCaption(IntPtr ZeroOnly, string lpWindowName);

    [DllImport("user32.dll")]
    static extern IntPtr GetMenu(IntPtr hWnd);

    [DllImport("user32.dll")]
    static extern int GetMenuItemCount(IntPtr hMenu);

    [DllImport("user32.dll")]
    static extern bool DrawMenuBar(IntPtr hWnd);

    [DllImport("user32.dll")]
    static extern bool RemoveMenu(IntPtr hMenu, uint uPosition, uint uFlags);

    public static uint MF_BYPOSITION = 0x400;
    public static uint MF_REMOVE = 0x1000;

    public static void WindowsReStyle() {
        Process[] Procs = Process.GetProcesses();
        foreach (Process proc in Procs) {

            if (proc.ProcessName.StartsWith("notepad")) {
                //get menu
                IntPtr HMENU = GetMenu(proc.MainWindowHandle);
                //get item count
                int count = GetMenuItemCount(HMENU);
                //loop & remove
                for (int i = 0; i < count; i++)
                    RemoveMenu(HMENU, 0, (MF_BYPOSITION | MF_REMOVE));

                //force a redraw
                DrawMenuBar(proc.MainWindowHandle);
            }
        }
    }