服务中访问当前用户注册表信息

　　Windows Vista后有session 0隔离机制，那么在服务中是不能直接访问当前登录用户的注册表信息的，因为此时的HKEY_CURRENT_USER是里面是system的。那么实在需要，该怎么做呢？方法还是有的，在网上搜了一下，如下两个链接提供了一些方法：

　　http://blog.csdn.net/zwh37333/article/details/6358725

　　http://blog.csdn.net/ly402609921/article/details/9127959

但是很不幸，我要用C#来实现这个过程，我不知道怎么去定义包含SID信息的结构体,但这里的关键就是获取SID，有了它就可以找到要访问的注册表了。所以最后不得不另想他法。不过还真想到了，也借鉴了以上两个帖子中的东西。

我的方法：

　　1.C#中有API可以在当前用户的上下文获取当前用户的SID；

　　2.在服务中模拟当前用户的上下文，获取SID，注意获取完切回来哦；

　　3.去HKEY_USERS下SID[SubKeyPath]下访问所需的注册表信息。

C#代码：

using System;
using System.Security;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Security.Principal;
using Microsoft.Win32;

namespace Toolkit
{
    public class AccessCurrentUserReg
    {
        #region Win32 API Imports

        [DllImport("Advapi32.dll", EntryPoint = "ImpersonateLoggedOnUser", SetLastError = true)]
        private static extern bool ImpersonateLoggedOnUser(IntPtr hToken);

        [DllImport("Advapi32.dll", EntryPoint = "RevertToSelf", SetLastError = true)]
        private static extern bool RevertToSelf();
        
        [DllImport("kernel32.dll", EntryPoint = "CloseHandle", SetLastError = true)]
        public static extern bool CloseHandle(IntPtr hSnapshot);

        [DllImport("kernel32.dll", EntryPoint = "WTSGetActiveConsoleSessionId")]
        private static extern uint WTSGetActiveConsoleSessionId();

        [DllImport("Wtsapi32.dll", EntryPoint = "WTSQueryUserToken", SetLastError = true)]
        private static extern bool WTSQueryUserToken(uint SessionId, ref IntPtr hToken);
        #endregion


        public static bool ReadCurrentUserReg(string RegPath, string SubKey, ref string KeyValue)
        {
            string CurrentUserSID = string.Empty;
            if (GetCurrentUserSID(ref CurrentUserSID))
            {
                RegistryKey rsg = Registry.Users.OpenSubKey(CurrentUserSID + "\" + RegPath, false);//false表只读
                KeyValue = (string)rsg.GetValue(SubKey);
                rsg.Close();
                return true;
            }
            return false;
        }

        public static bool GetCurrentUserSID(ref string CurrentUserSID)
        {
            IntPtr hUserToken = IntPtr.Zero;
            if (ApplicationLoader.GetCurrentUserToken(ref hUserToken))
            {
                if (!ImpersonateLoggedOnUser(hUserToken))//Impersonate Current User logon
                {
                    return false;
                }
                CloseHandle(hUserToken);

                //Obtain Current user SID
                WindowsIdentity windowsIdentity = WindowsIdentity.GetCurrent();
                CurrentUserSID = windowsIdentity.User.ToString();

                if (!RevertToSelf())//come back
                {
                    LoggerLib.Logger.WriteLog(LoggerLib.Logger.EventSeverity.NOTIFY_SEVERITY_EMERG, string.Format("RevertToSelf()failed!"));
                }
                return true;
            }
            return false;
        }
        
        public static bool GetCurrentUserToken(ref IntPtr hCurrentUserToken)
        {
            // obtain the currently active session id; every logged on user in the system has a unique session id
            uint dwSessionId = WTSGetActiveConsoleSessionId();

            if (!WTSQueryUserToken(dwSessionId, ref hCurrentUserToken))
            {                
                return false;
            }
            return true;
        }
    }
}

　　代码里只实现了读取注册表的信息，改写和写入类似。