C# 通过服务守护前台带有界面的应用程序

如果直接在服务中执行带有UI的应用将会把应用归为后台应用，无法看到UI的，以下方法可以有效解决看不到UI的问题.

        private void StartService(string appName)
        {
            try
            {        
				
                string watchexepath = toWatchServicePath;
                string serviceName = toWatchServicePath + "\\" + appName+".exe"; 

                UserProcess.PROCESS_INFORMATION processInfo;
                UserProcess.StartProcessAndBypassUAC(serviceName, "", out processInfo);                                

                LogHelper.WriteLog("已重启", serviceName);

            }
            catch (Exception ex)
            {
                LogHelper.WriteLog("启动时错误", ex.Message);
            }
        }

　　UserProcess类如下：

    class UserProcess
    {
        #region Structures


        [StructLayout(LayoutKind.Sequential)]
        public struct SECURITY_ATTRIBUTES
        {
            public int Length;
            public IntPtr lpSecurityDescriptor;
            public bool bInheritHandle;
        }


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


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


        #endregion


        #region Enumerations


        enum TOKEN_TYPE : int
        {
            TokenPrimary = 1,
            TokenImpersonation = 2
        }


        enum SECURITY_IMPERSONATION_LEVEL : int
        {
            SecurityAnonymous = 0,
            SecurityIdentification = 1,
            SecurityImpersonation = 2,
            SecurityDelegation = 3,
        }


        enum WTSInfoClass
        {
            InitialProgram,
            ApplicationName,
            WorkingDirectory,
            OEMId,
            SessionId,
            UserName,
            WinStationName,
            DomainName,
            ConnectState,
            ClientBuildNumber,
            ClientName,
            ClientDirectory,
            ClientProductId,
            ClientHardwareId,
            ClientAddress,
            ClientDisplay,
            ClientProtocolType
        }


        #endregion


        #region Constants


        public const int TOKEN_DUPLICATE = 0x0002;
        public const uint MAXIMUM_ALLOWED = 0x2000000;
        public const int CREATE_NEW_CONSOLE = 0x00000010;


        public const int IDLE_PRIORITY_CLASS = 0x40;
        public const int NORMAL_PRIORITY_CLASS = 0x20;
        public const int HIGH_PRIORITY_CLASS = 0x80;
        public const int REALTIME_PRIORITY_CLASS = 0x100;


        #endregion


        #region Win32 API Imports


        [DllImport("kernel32.dll", SetLastError = true)]
        private static extern bool CloseHandle(IntPtr hSnapshot);


        [DllImport("kernel32.dll")]
        static extern uint WTSGetActiveConsoleSessionId();


        [DllImport("wtsapi32.dll", CharSet = CharSet.Unicode, SetLastError = true), SuppressUnmanagedCodeSecurityAttribute]
        static extern bool WTSQuerySessionInformation(System.IntPtr hServer, int sessionId, WTSInfoClass wtsInfoClass, out System.IntPtr ppBuffer, out uint pBytesReturned);


        [DllImport("advapi32.dll", EntryPoint = "CreateProcessAsUser", SetLastError = true, CharSet = CharSet.Ansi, CallingConvention = CallingConvention.StdCall)]
        public extern static bool CreateProcessAsUser(IntPtr hToken, String lpApplicationName, String lpCommandLine, ref SECURITY_ATTRIBUTES lpProcessAttributes,
            ref SECURITY_ATTRIBUTES lpThreadAttributes, bool bInheritHandle, int dwCreationFlags, IntPtr lpEnvironment,
            String lpCurrentDirectory, ref STARTUPINFO lpStartupInfo, out PROCESS_INFORMATION lpProcessInformation);


        [DllImport("kernel32.dll")]
        static extern bool ProcessIdToSessionId(uint dwProcessId, ref uint pSessionId);


        [DllImport("advapi32.dll", EntryPoint = "DuplicateTokenEx")]
        public extern static bool DuplicateTokenEx(IntPtr ExistingTokenHandle, uint dwDesiredAccess,
            ref SECURITY_ATTRIBUTES lpThreadAttributes, int TokenType,
            int ImpersonationLevel, ref IntPtr DuplicateTokenHandle);


        [DllImport("kernel32.dll")]
        static extern IntPtr OpenProcess(uint dwDesiredAccess, bool bInheritHandle, uint dwProcessId);


        [DllImport("advapi32", SetLastError = true), SuppressUnmanagedCodeSecurityAttribute]
        static extern bool OpenProcessToken(IntPtr ProcessHandle, int DesiredAccess, ref IntPtr TokenHandle);


        #endregion


        public static string GetCurrentActiveUser()
        {
            IntPtr hServer = IntPtr.Zero, state = IntPtr.Zero;
            uint bCount = 0;


            
            uint dwSessionId = WTSGetActiveConsoleSessionId();
            string domain = string.Empty, userName = string.Empty;


            if (WTSQuerySessionInformation(hServer, (int)dwSessionId, WTSInfoClass.DomainName, out state, out bCount))
            {
                domain = Marshal.PtrToStringAuto(state);
            }


            if (WTSQuerySessionInformation(hServer, (int)dwSessionId, WTSInfoClass.UserName, out state, out bCount))
            {
                userName = Marshal.PtrToStringAuto(state);
            }


            return string.Format("{0}\\{1}", domain, userName);
        }


       
        public static bool StartProcessAndBypassUAC(String applicationName, String command, out PROCESS_INFORMATION procInfo)
        {
            uint winlogonPid = 0;
            IntPtr hUserTokenDup = IntPtr.Zero, hPToken = IntPtr.Zero, hProcess = IntPtr.Zero;
            procInfo = new PROCESS_INFORMATION();


            
            uint dwSessionId = WTSGetActiveConsoleSessionId();


          
            Process[] processes = Process.GetProcessesByName("winlogon");
            foreach (Process p in processes)
            {
                if ((uint)p.SessionId == dwSessionId)
                {
                    winlogonPid = (uint)p.Id;
                }
            }


           
            hProcess = OpenProcess(MAXIMUM_ALLOWED, false, winlogonPid);


            
            if (!OpenProcessToken(hProcess, TOKEN_DUPLICATE, ref hPToken))
            {
                CloseHandle(hProcess);
                return false;
            }


           
            SECURITY_ATTRIBUTES sa = new SECURITY_ATTRIBUTES();
            sa.Length = Marshal.SizeOf(sa);


            
            if (!DuplicateTokenEx(hPToken, MAXIMUM_ALLOWED, ref sa, (int)SECURITY_IMPERSONATION_LEVEL.SecurityIdentification, (int)TOKEN_TYPE.TokenPrimary, ref hUserTokenDup))
            {
                CloseHandle(hProcess);
                CloseHandle(hPToken);
                return false;
            }


          
            STARTUPINFO si = new STARTUPINFO();
            si.cb = (int)Marshal.SizeOf(si);
            si.lpDesktop = @"winsta0\default"; 


            
            int dwCreationFlags = NORMAL_PRIORITY_CLASS | CREATE_NEW_CONSOLE;


          
            bool result = CreateProcessAsUser(hUserTokenDup,        
                                            applicationName,        
                                            command,                
                                            ref sa,                 
                                            ref sa,                 
                                            false,                  
                                            dwCreationFlags,        
                                            IntPtr.Zero,            
                                            null,                   
                                            ref si,                 
                                            out procInfo            
                                            );


           
            CloseHandle(hProcess);
            CloseHandle(hPToken);
            CloseHandle(hUserTokenDup);


            return result; 
        }
    }