Create new desctop C#

/*
 * Created by SharpDevelop.
 * User: Administrator
 * Date: 23.09.2013
 * Time: 12:32
 *
 * To change this template use Tools | Options | Coding | Edit Standard Headers.
 */
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Runtime.InteropServices;
using System.ComponentModel;
using System.Threading;

namespace ScreenBlock
{
    /// <summary>
    /// Description of Block.
    /// </summary>



    internal class Block
    {

        // Fields
        private const uint GENERIC_ALL = 0x1ff;

        [DllImport("user32.dll", SetLastError = true)]
        [return: MarshalAs(UnmanagedType.Bool)]
        private static extern bool CloseDesktop ( IntPtr hDesktop );

        [DllImport("user32.dll", SetLastError = true)]
        [return: MarshalAs(UnmanagedType.Bool)]
        private static extern bool CloseWindowStation ( IntPtr hWinSta );

        [DllImport("user32.dll", SetLastError = true)]
        private static extern IntPtr CreateDesktop ( string lpszDesktop, string lpszDevice, IntPtr pDevmode, uint dwFlags, uint dwDesiredAccess, IntPtr Zero );

        [DllImport("kernel32.dll", SetLastError = true)]
        [return: MarshalAs(UnmanagedType.Bool)]
        private static extern bool CreateProcess ( string lpApplicationName, string lpCommandLine, IntPtr pcZero, IntPtr thZero, bool bInheritHandles, uint dwCreationFlags, IntPtr lpEnvironment, string lpCurrentDirectory, ref STARTUPINFO lpStartupInfo, out PROCESS_INFORMATION lpProcessInformation );

        [DllImport("user32.dll", SetLastError = true)]
        private static extern IntPtr CreateWindowStation ( string lpWinSta, uint dwFlags, uint acessMask, IntPtr zero );

        [DllImport("user32.dll", SetLastError = true)]
        [return: MarshalAs(UnmanagedType.Bool)]
        private static extern bool EnumWindows ( EnumProc lpEnumProc, IntPtr lParam );

        [DllImport("user32.dll", SetLastError = true)]
        private static extern IntPtr FindWindow ( string cap, string cls );

        [DllImport("user32.dll", SetLastError = true)]
        private static extern IntPtr GetProcessWindowStation ();

        [DllImport("user32.dll", SetLastError = true)]
        private static extern IntPtr GetThreadDesktop ( int thId );

        [DllImport("user32.dll", SetLastError = true)]
        private static extern int GetWindowText ( IntPtr hWnd, StringBuilder sb, int max );

        [DllImport("user32.dll", SetLastError = true)]
        [return: MarshalAs(UnmanagedType.Bool)]
        private static extern bool SwitchDesktop ( IntPtr hDesktop );

        [DllImport("user32.dll", SetLastError = true)]
        private static extern IntPtr OpenInputDesktop ( uint dwFlags, bool Inherit, uint dwDesiredAccess );

        [DllImport("user32.dll", SetLastError = true)]
        [return: MarshalAs(UnmanagedType.Bool)]
        private static extern bool SetProcessWindowStation ( IntPtr hWinSta );

        [DllImport("user32.dll", SetLastError = true)]
        [return: MarshalAs(UnmanagedType.Bool)]
        private static extern bool SetThreadDesktop ( IntPtr hDesktop );


        // Nested Types
        private delegate bool EnumProc ( IntPtr hWnd, IntPtr lParam );

        [StructLayout(LayoutKind.Sequential)]
        internal struct PROCESS_INFORMATION
        {
            public IntPtr hProcess;
            public IntPtr hThread;
            public int dwProcessId;
            public int dwThreadId;
        }

        [StructLayout(LayoutKind.Sequential)]
        private struct STARTUPINFO
        {
            public int cb;
            public string lpReserved;
            public string lpDesktop;
            public string lpTitle;
            public int dwX;
            public int dwY;
            public int dwXSize;
            public int dwYSize;
            public int dwXCountChars;
            public int dwYCountChars;
            public int dwFillAttribute;
            public int dwFlags;
            public short wShowWindow;
            public short cbReserved2;
            public IntPtr lpReserved2;
            public IntPtr hStdInput;
            public IntPtr hStdOutput;
            public IntPtr hStdError;

        public static void Block()
        {
            int num;
            string temp;
            IntPtr hObject = CreateDesktop("NewDesktop", null, IntPtr.Zero, 1, 0x1ff, IntPtr.Zero);
            if (!SUCCESS(hObject)) {
                throw new Win32Exception(_geterr());
            }
            if (!SetThreadDesktop(hObject) && ((num = _geterr()) != 0)) {
                throw new Win32Exception(num);
            }
            IntPtr hDesktop = OpenInputDesktop(1, false, 0x1ff);
            if (!SwitchDesktop(hObject) && ((num = _geterr()) != 0)) {
                throw new Win32Exception(num);
            }
            _shell(Environment.GetEnvironmentVariable("windir") + @"\notepad.exe", "NewDesktop");
            Thread.Sleep(0x1388);

            EnumWindows(delegate( IntPtr hWnd, IntPtr lParam ) {
                if (!string.IsNullOrEmpty(temp = _getwincap(hWnd))) {
                    Console.WriteLine(temp);
                }
                return true;
            }, IntPtr.Zero);

            Thread.Sleep(0x3e8);
            if (!SwitchDesktop(hDesktop) && ((num = _geterr()) != 0)) {
                throw new Win32Exception(num);
            }
            if (!SetThreadDesktop(hDesktop) && ((num = _geterr()) != 0)) {
                throw new Win32Exception(num);
            }
            if (!CloseDesktop(hObject) && ((num = _geterr()) != 0))
                throw new Win32Exception(num);
            Console.Read();
        }

        private static int _geterr () {
            return Marshal.GetLastWin32Error();
        }

        private static string _getwincap ( IntPtr hWnd ) {
            StringBuilder sb = new StringBuilder(0xff);
            int length = GetWindowText(hWnd, sb, sb.Capacity);
            return sb.ToString(0, length);
        }

        private static void _shell ( string file, string desktop ) {
            STARTUPINFO startupinfo;
            PROCESS_INFORMATION process_information;
            int num;
            startupinfo = new STARTUPINFO {
                cb = Marshal.SizeOf(typeof(STARTUPINFO)),
                lpDesktop = desktop
            };
            if (!CreateProcess(file, null, IntPtr.Zero, IntPtr.Zero, false, 0x20, IntPtr.Zero, null, ref startupinfo, out process_information) && ((num = _geterr()) != 0)) {
                throw new Win32Exception(num);
            }
        }

        private static bool SUCCESS ( IntPtr hObject ) {
            return (hObject != IntPtr.Zero);
        }

        }
    }
}