C# - Windows服务获取当前记录的用户桌面目录路径

时间:2016-01-25 12:41:03

标签: c# windows-services

在“本地系统”下运行Windows服务应用程序时,我在获取当前Windows登录用户桌面文件夹时遇到问题。 当我尝试使用时:

Environment.GetFolderPath(Environment.SpecialFolder.Desktop);

我得到一个空字符串(我猜是因为我在“本地系统”下运行该服务)。

这是我的OnStart功能:

protected override void OnStart(string[] args)
{
    System.Diagnostics.Debugger.Launch();

    //Get the current user desktop path;
    string path = Environment.GetFolderPath(Environment.SpecialFolder.Desktop);
    string filter = "*.*";

    // create the watcher.
    FileSystemWatcher watcher = new FileSystemWatcher(path, filter)
    {
        EnableRaisingEvents = true,
        IncludeSubdirectories = true

    };
    //listen to the change event;
    watcher.Changed += watcher_Changed;
    //Thread.Sleep(Timeout.Infinite);
}

有没有办法获取当前记录的Windows用户路径?

感谢。

2 个答案:

答案 0 :(得分:3)

即使并非总是默认情况下,Windows允许登录多个用户。

您需要调用三个函数:

1)使用WTSEnumerateSessions获取(所有)活动会话。 在this question中调用的一个很好的例子。您可以使用“localhost”作为servername参数。

2)获取WTSQueryUserToken(每个)会话的令牌 应该是直截了当的,不要忘记内存管理。

3)使用(每个)令牌查询SHGetKnownFolderPath。 (来自pinvoke.net的一些相关剪贴画):

public static readonly Guid Desktop = new Guid( "B4BFCC3A-DB2C-424C-B029-7FE99A87C641" );

public static readonly Guid PublicDesktop = new Guid( "C4AA340D-F20F-4863-AFEF-F87EF2E6BA25" );

IntPtr token = AllWTSQueryUserTokens().First(); // <-- Your implementation
IntPtr pPath;
if ( SHGetKnownFolderPath(PublicDesktop, 0, token, out pPath ) == 0 )
{
    string s = System.Runtime.InteropServices.Marshal.PtrToStringUni( pPath );
    System.Runtime.InteropServices.Marshal.FreeCoTaskMem( pPath );
    // s now contains the path for the all-users "Public Desktop" folder
}
// Release memory (token)!

将这三者结合在一起是一项非常重要的工作,并且需要进行大量的测试和内存管理,并将其作为OP的练习。

在测试解决方案时请注意caveats with 32bit/64bit registry issues

此外,您应该阅读this问题以获取更多信息。

答案 1 :(得分:0)

您可以使用服务中的以下代码来使用任何CSIDL获取特殊文件夹。对于桌面目录,您应该将CSIDL_LOCAL_APPDATA替换为CSIDL_DESKTOPDIRECTORY

可以查找

Pinvoke.net以在C#中导入winapi方法。

public static String GetUserPath()
{
    var hUserToken = IntPtr.Zero;
    IntPtr pidlist = IntPtr.Zero;
    StringBuilder sb = new StringBuilder(MAX_PATH);

    GetSessionUserToken(ref hUserToken);
    SHGetFolderLocation(IntPtr.Zero, CSIDL_LOCAL_APPDATA, hUserToken, 0, out pidlist);
    SHGetPathFromIDListW(pidlist, sb);

    return sb.ToString();
}

private static bool GetSessionUserToken(ref IntPtr phUserToken)
{
    var bResult = false;
    var hImpersonationToken = IntPtr.Zero;
    var activeSessionId = INVALID_SESSION_ID;
    var pSessionInfo = IntPtr.Zero;
    var sessionCount = 0;

    // Get a handle to the user access token for the current active session.
    if (WTSEnumerateSessions(WTS_CURRENT_SERVER_HANDLE, 0, 1, ref pSessionInfo, ref sessionCount) != 0)
    {
        var arrayElementSize = Marshal.SizeOf(typeof(WTS_SESSION_INFO));
        var current = pSessionInfo;

        for (var i = 0; i < sessionCount; i++)
        {
            var si = (WTS_SESSION_INFO)Marshal.PtrToStructure((IntPtr)current, typeof(WTS_SESSION_INFO));
            //current = new IntPtr(current.ToInt64() + arrayElementSize);
            current = (IntPtr)((long)current + arrayElementSize); // should be same as above line

            if (si.State == WTS_CONNECTSTATE_CLASS.WTSActive)
            {
                activeSessionId = si.SessionID;
            }
        }
    }

    // If enumerating did not work, fall back to the old method
    if (activeSessionId == INVALID_SESSION_ID)
    {
        activeSessionId = WTSGetActiveConsoleSessionId();
    }

    SECURITY_ATTRIBUTES sa = new SECURITY_ATTRIBUTES();
    sa.nLength = Marshal.SizeOf(sa);
    if (WTSQueryUserToken(activeSessionId, ref hImpersonationToken) != 0)
    {
        // Convert the impersonation token to a primary token
        bResult = DuplicateTokenEx(
            hImpersonationToken, 
            0, 
            ref sa,//IntPtr.Zero,
            (int)SECURITY_IMPERSONATION_LEVEL.SecurityDelegation,
            (int)TOKEN_TYPE.TokenPrimary,
            ref phUserToken);

        CloseHandle(hImpersonationToken);
    }

    return bResult;
}

private const int CSIDL_LOCAL_APPDATA = 0x001c;
private const int MAX_PATH = 260;