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关于c#：以编程方式确定锁定工作站的持续时间？

2023-04-14 06:40:00

Programmatically Determine a Duration of a Locked Workstation?

如何用代码确定机器被锁定了多长时间？

也欢迎使用C#之外的其他想法。

我喜欢Windows服务的想法(并且已经接受了它)是为了简洁和整洁，但是不幸的是，我认为在这种情况下它不会对我有用。我想在办公室而不是在家(或者我想在家中)上在工作站上运行它，但是出于国防部的考虑，它的工作受到了很大的限制。这实际上就是我自己滚动自己的原因的一部分。

我还是把它写出来，看看它是否有效。谢谢大家！

我以前没有发现过，但是从任何应用程序中，您都可以连接SessionSwitchEventHandler。显然，您的应用程序将需要运行，但是只要它是：

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Microsoft.Win32.SystemEvents.SessionSwitch += new Microsoft.Win32.SessionSwitchEventHandler(SystemEvents_SessionSwitch);

void SystemEvents_SessionSwitch(object sender, Microsoft.Win32.SessionSwitchEventArgs e)
{
if (e.Reason == SessionSwitchReason.SessionLock)
{
//I left my desk
}
else if (e.Reason == SessionSwitchReason.SessionUnlock)
{
//I returned to my desk
}
}

我将创建一个Windows Service(Visual Studio 2005项目类型)来处理OnSessionChange事件，如下所示：

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protected override void OnSessionChange(SessionChangeDescription changeDescription)
{
if (changeDescription.Reason == SessionChangeReason.SessionLock)
{
//I left my desk
}
else if (changeDescription.Reason == SessionChangeReason.SessionUnlock)
{
//I returned to my desk
}
}

此时，您如何记录活动以及如何记录活动取决于您，但是Windows服务可提供对Windows事件(如启动，关闭，登录/注销以及锁定和解锁事件)的快速便捷访问。

下面的解决方案使用Win32 API。工作站锁定时调用OnSessionLock，解锁时调用OnSessionUnlock。

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[DllImport("wtsapi32.dll")]
private static extern bool WTSRegisterSessionNotification(IntPtr hWnd,
int dwFlags);

[DllImport("wtsapi32.dll")]
private static extern bool WTSUnRegisterSessionNotification(IntPtr
hWnd);

private const int NotifyForThisSession = 0; // This session only

private const int SessionChangeMessage = 0x02B1;
private const int SessionLockParam = 0x7;
private const int SessionUnlockParam = 0x8;

protected override void WndProc(ref Message m)
{
// check for session change notifications
if (m.Msg == SessionChangeMessage)
{
if (m.WParam.ToInt32() == SessionLockParam)
OnSessionLock(); // Do something when locked
else if (m.WParam.ToInt32() == SessionUnlockParam)
OnSessionUnlock(); // Do something when unlocked
}

base.WndProc(ref m);
return;
}

void OnSessionLock()
{
Debug.WriteLine("Locked...");
}

void OnSessionUnlock()
{
Debug.WriteLine("Unlocked...");
}

private void Form1Load(object sender, EventArgs e)
{
WTSRegisterSessionNotification(this.Handle, NotifyForThisSession);
}

// and then when we are done, we should unregister for the notification
// WTSUnRegisterSessionNotification(this.Handle);

我知道这是一个老问题，但是我找到了一种获取给定会话的锁定状态的方法。

我在这里找到了答案，但是它是用C语言编写的，所以我尽可能地将其翻译为C#以获取锁定状态。

所以去了：

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static class SessionInfo {
private const Int32 FALSE = 0;

private static readonly IntPtr WTS_CURRENT_SERVER = IntPtr.Zero;

private const Int32 WTS_SESSIONSTATE_LOCK = 0;
private const Int32 WTS_SESSIONSTATE_UNLOCK = 1;

private static bool _is_win7 = false;

static SessionInfo() {
var os_version = Environment.OSVersion;
_is_win7 = (os_version.Platform == PlatformID.Win32NT && os_version.Version.Major == 6 && os_version.Version.Minor == 1);
}

[DllImport("wtsapi32.dll")]
private static extern Int32 WTSQuerySessionInformation(
IntPtr hServer,
[MarshalAs(UnmanagedType.U4)] UInt32 SessionId,
[MarshalAs(UnmanagedType.U4)] WTS_INFO_CLASS WTSInfoClass,
out IntPtr ppBuffer,
[MarshalAs(UnmanagedType.U4)] out UInt32 pBytesReturned
);

[DllImport("wtsapi32.dll")]
private static extern void WTSFreeMemoryEx(
WTS_TYPE_CLASS WTSTypeClass,
IntPtr pMemory,
UInt32 NumberOfEntries
);

private enum WTS_INFO_CLASS {
WTSInitialProgram = 0,
WTSApplicationName = 1,
WTSWorkingDirectory = 2,
WTSOEMId = 3,
WTSSessionId = 4,
WTSUserName = 5,
WTSWinStationName = 6,
WTSDomainName = 7,
WTSConnectState = 8,
WTSClientBuildNumber = 9,
WTSClientName = 10,
WTSClientDirectory = 11,
WTSClientProductId = 12,
WTSClientHardwareId = 13,
WTSClientAddress = 14,
WTSClientDisplay = 15,
WTSClientProtocolType = 16,
WTSIdleTime = 17,
WTSLogonTime = 18,
WTSIncomingBytes = 19,
WTSOutgoingBytes = 20,
WTSIncomingFrames = 21,
WTSOutgoingFrames = 22,
WTSClientInfo = 23,
WTSSessionInfo = 24,
WTSSessionInfoEx = 25,
WTSConfigInfo = 26,
WTSValidationInfo = 27,
WTSSessionAddressV4 = 28,
WTSIsRemoteSession = 29
}

private enum WTS_TYPE_CLASS {
WTSTypeProcessInfoLevel0,
WTSTypeProcessInfoLevel1,
WTSTypeSessionInfoLevel1
}

public enum WTS_CONNECTSTATE_CLASS {
WTSActive,
WTSConnected,
WTSConnectQuery,
WTSShadow,
WTSDisconnected,
WTSIdle,
WTSListen,
WTSReset,
WTSDown,
WTSInit
}

public enum LockState {
Unknown,
Locked,
Unlocked
}

[StructLayout(LayoutKind.Sequential)]
private struct WTSINFOEX {
public UInt32 Level;
public UInt32 Reserved; /* I have observed the Data field is pushed down by 4 bytes so i have added this field as padding. */
public WTSINFOEX_LEVEL Data;
}

[StructLayout(LayoutKind.Sequential)]
private struct WTSINFOEX_LEVEL {
public WTSINFOEX_LEVEL1 WTSInfoExLevel1;
}

[StructLayout(LayoutKind.Sequential)]
private struct WTSINFOEX_LEVEL1 {
public UInt32 SessionId;
public WTS_CONNECTSTATE_CLASS SessionState;
public Int32 SessionFlags;

/* I can't figure out what the rest of the struct should look like but as i don't need anything past the SessionFlags i'm not going to. */

}

public static LockState GetSessionLockState(UInt32 session_id) {
IntPtr ppBuffer;
UInt32 pBytesReturned;

Int32 result = WTSQuerySessionInformation(
WTS_CURRENT_SERVER,
session_id,
WTS_INFO_CLASS.WTSSessionInfoEx,
out ppBuffer,
out pBytesReturned
);

if (result == FALSE)
return LockState.Unknown;

var session_info_ex = Marshal.PtrToStructure<WTSINFOEX>(ppBuffer);

if (session_info_ex.Level != 1)
return LockState.Unknown;

var lock_state = session_info_ex.Data.WTSInfoExLevel1.SessionFlags;
WTSFreeMemoryEx(WTS_TYPE_CLASS.WTSTypeSessionInfoLevel1, ppBuffer, pBytesReturned);

if (_is_win7) {
/* Ref: https://msdn.microsoft.com/en-us/library/windows/desktop/ee621019(v=vs.85).aspx
* Windows Server 2008 R2 and Windows 7: Due to a code defect, the usage of the WTS_SESSIONSTATE_LOCK
* and WTS_SESSIONSTATE_UNLOCK flags is reversed. That is, WTS_SESSIONSTATE_LOCK indicates that the
* session is unlocked, and WTS_SESSIONSTATE_UNLOCK indicates the session is locked.
* */
switch (lock_state) {
case WTS_SESSIONSTATE_LOCK:
return LockState.Unlocked;

case WTS_SESSIONSTATE_UNLOCK:
return LockState.Locked;

default:
return LockState.Unknown;
}
}
else {
switch (lock_state) {
case WTS_SESSIONSTATE_LOCK:
return LockState.Locked;

case WTS_SESSIONSTATE_UNLOCK:
return LockState.Unlocked;

default:
return LockState.Unknown;
}
}
}
}

注意：上面的代码是从一个更大的项目中提取的，所以如果我错过了一点抱歉。我没有时间测试上面的代码，但计划在一两周后回来检查所有内容。我现在才发布它是因为我不想忘记这样做。

如果您有兴趣编写Windows服务以"发现"这些事件，请使用topshelf(使编写Windows服务更加容易的库/框架)。

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public interface IMyServiceContract
{
void Start();

void Stop();

void SessionChanged(Topshelf.SessionChangedArguments args);
}

public class MyService : IMyServiceContract
{

public void Start()
{
}

public void Stop()
{

}

public void SessionChanged(SessionChangedArguments e)
{
Console.WriteLine(e.ReasonCode);
}
}

，现在是将topshelf服务连接到上面的接口/混凝土的代码

除了我标记为

的两行外，以下所有内容均为"典型" topshelf设置...。

/ *这是魔术线* /

这些是激发SessionChanged方法的原因。

我在Windows 10 x64上对此进行了测试。我锁定并解锁了机器，并得到了预期的结果。

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IMyServiceContract myServiceObject = new MyService(); /* container.Resolve<IMyServiceContract>(); */

HostFactory.Run(x =>
{
x.Service<IMyServiceContract>(s =>
{
s.ConstructUsing(name => myServiceObject);
s.WhenStarted(sw => sw.Start());
s.WhenStopped(sw => sw.Stop());
s.WhenSessionChanged((csm, hc, chg) => csm.SessionChanged(chg)); /* THIS IS MAGIC LINE */
});

x.EnableSessionChanged(); /* THIS IS MAGIC LINE */

/* use command line variables for the below commented out properties */
/*
x.RunAsLocalService();
x.SetDescription("My Description");
x.SetDisplayName("My Display Name");
x.SetServiceName("My Service Name");
x.SetInstanceName("My Instance");
*/

x.StartManually(); // Start the service manually. This allows the identity to be tweaked before the service actually starts

/* the below map to the"Recover" tab on the properties of the Windows Service in Control Panel */
x.EnableServiceRecovery(r =>
{
r.OnCrashOnly();
r.RestartService(1); ////first
r.RestartService(1); ////second
r.RestartService(1); ////subsequents
r.SetResetPeriod(0);
});

x.DependsOnEventLog(); // Windows Event Log
x.UseLog4Net();

x.EnableShutdown();

x.OnException(ex =>
{
/* Log the exception */
/* not seen, I have a log4net logger here */
});
});

我的packages.config提供有关版本的提示：

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注意：这不是答案，而是对Timothy Carter答案的(贡献)，因为到目前为止，我的声誉不允许我发表评论。

以防万一有人尝试了Timothy Carter的答案中的代码，并且没有立即在Windows服务中使它正常工作，则需要在的构造函数中将一个属性设置为true。服务。
只需在构造函数中添加以下行：

1	CanHandleSessionChangeEvent = true;

并确保在启动服务后不要设置此属性，否则将抛出InvalidOperationException。

在Windows Task Scheduler中，您可以创建触发on workstation lock和on workstation unlock的任务。每个任务都可以将标记和时间戳记写入文件，以表明工作站是被锁定还是未锁定以及它何时发生。

我意识到这不是编程方式。它比编写服务更简单。它不会丢失任何事件，因为在锁定/解锁转换时您的程序恰巧没有运行。

下面是100％工作代码，用于查找PC??是否已锁定。

在使用此名称之前，请使用名称空间System.Runtime.InteropServices。

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[DllImport("user32", EntryPoint ="OpenDesktopA", CharSet = CharSet.Ansi,SetLastError = true, ExactSpelling = true)]
private static extern Int32 OpenDesktop(string lpszDesktop, Int32 dwFlags, bool fInherit, Int32 dwDesiredAccess);

[DllImport("user32", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern Int32 CloseDesktop(Int32 hDesktop);

[DllImport("user32", CharSet = CharSet.Ansi,SetLastError = true,ExactSpelling = true)]
private static extern Int32 SwitchDesktop(Int32 hDesktop);

public static bool IsWorkstationLocked()
{
const int DESKTOP_SWITCHDESKTOP = 256;
int hwnd = -1;
int rtn = -1;

hwnd = OpenDesktop("Default", 0, false, DESKTOP_SWITCHDESKTOP);

if (hwnd != 0)
{
rtn = SwitchDesktop(hwnd);
if (rtn == 0)
{
// Locked
CloseDesktop(hwnd);
return true;
}
else
{
// Not locked
CloseDesktop(hwnd);
}
}
else
{
// Error:"Could not access the desktop..."
}

return false;
}

锁定工作站编程服务