在 Windows 服务中，我尝试使用来自外部 DLL 的方法来显示 UI（它不请求任何用户输入）。我读到您不能从 Windows 服务（自 Vista 起）与 UI 进行交互，因为它在与用户不同的会话中运行（这是唯一可以与 UI 交互的人）。但是可以从服务启动交互式进程，如this article所示，我测试过，它可以工作。
所以我想也许我可以通过使用活动用户的会话以类似的方式调用该 DLL 的方法，然后在服务上获取返回的数据......任何指南或示例如何这样做？
我还尝试检查已安装服务的“登录”选项卡上的“允许系统与桌面交互”选项，并使用当前登录用户的用户帐户启动服务，但没有成功，它没有显示任何错误，但它应该显示一个窗口并且没有显示任何内容。
【问题讨论】：
标签： c# service windows-services
您不能只从 Windows 服务调用 UI，因为它在 0 会话中运行。要调用 UI，您需要将会话更改为当前用户的会话。这是链接如何做到这一点
https://www.codeproject.com/kb/vista-security/subvertingvistauac.aspx
【讨论】：
您已经阅读并了解 service session(0) 如何不允许您在 UI 上调用任何在不同会话上运行的东西。 我曾经在 PInvoke 周围使用过一个 API 包装器，它有一个名为“CreateProcessAsUser”的方法。它所做的是，它获取当前记录用户会话的令牌并使用该会话启动一个进程。为了启动进程，应该有一个正在运行的活动桌面会话。
这是完整的代码：https://gist.github.com/vendettamit/a518bceef3678963c5fd
这有点 hack，但它也是一个很好的解决方法。您可以通过自己的流程包装器启动第三方方法。
【讨论】：
通常 windows 服务无法与 UI 交互，因为 UI 将在用户会话下运行，而服务将在系统下运行。所以您需要执行模拟并启动应用程序。
using System.Runtime.InteropServices;
using System;
using System.Diagnostics;
[StructLayout(LayoutKind.Sequential)]
internal struct PROCESS_INFORMATION
{
public IntPtr hProcess;
public IntPtr hThread;
public uint dwProcessId;
public uint dwThreadId;
}
[StructLayout(LayoutKind.Sequential)]
internal struct SECURITY_ATTRIBUTES
{
public uint nLength;
public IntPtr lpSecurityDescriptor;
public bool bInheritHandle;
}
[StructLayout(LayoutKind.Sequential)]
public struct STARTUPINFO
{
public uint 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;
}
internal enum SECURITY_IMPERSONATION_LEVEL
{
SecurityAnonymous,
SecurityIdentification,
SecurityImpersonation,
SecurityDelegation
}
internal enum TOKEN_TYPE
{
TokenPrimary = 1,
TokenImpersonation
}
public class ProcessAsUser
{
[DllImport("advapi32.dll", SetLastError = true)]
private static extern bool CreateProcessAsUser(
IntPtr hToken,
string lpApplicationName,
string lpCommandLine,
ref SECURITY_ATTRIBUTES lpProcessAttributes,
ref SECURITY_ATTRIBUTES lpThreadAttributes,
bool bInheritHandles,
uint dwCreationFlags,
IntPtr lpEnvironment,
string lpCurrentDirectory,
ref STARTUPINFO lpStartupInfo,
out PROCESS_INFORMATION lpProcessInformation);
[DllImport("advapi32.dll", EntryPoint = "DuplicateTokenEx", SetLastError = true)]
private static extern bool DuplicateTokenEx(
IntPtr hExistingToken,
uint dwDesiredAccess,
ref SECURITY_ATTRIBUTES lpThreadAttributes,
Int32 ImpersonationLevel,
Int32 dwTokenType,
ref IntPtr phNewToken);
[DllImport("advapi32.dll", SetLastError = true)]
private static extern bool OpenProcessToken(
IntPtr ProcessHandle,
UInt32 DesiredAccess,
ref IntPtr TokenHandle);
[DllImport("userenv.dll", SetLastError = true)]
private static extern bool CreateEnvironmentBlock(
ref IntPtr lpEnvironment,
IntPtr hToken,
bool bInherit);
[DllImport("userenv.dll", SetLastError = true)]
private static extern bool DestroyEnvironmentBlock(
IntPtr lpEnvironment);
[DllImport("kernel32.dll", SetLastError = true)]
private static extern bool CloseHandle(
IntPtr hObject);
private const short SW_SHOW = 5;
private const uint TOKEN_QUERY = 0x0008;
private const uint TOKEN_DUPLICATE = 0x0002;
private const uint TOKEN_ASSIGN_PRIMARY = 0x0001;
private const int GENERIC_ALL_ACCESS = 0x10000000;
private const int STARTF_USESHOWWINDOW = 0x00000001;
private const int STARTF_FORCEONFEEDBACK = 0x00000040;
private const uint CREATE_UNICODE_ENVIRONMENT = 0x00000400;
private static bool LaunchProcessAsUser(string cmdLine, IntPtr token, IntPtr envBlock)
{
bool result = false;
PROCESS_INFORMATION pi = new PROCESS_INFORMATION();
SECURITY_ATTRIBUTES saProcess = new SECURITY_ATTRIBUTES();
SECURITY_ATTRIBUTES saThread = new SECURITY_ATTRIBUTES();
saProcess.nLength = (uint)Marshal.SizeOf(saProcess);
saThread.nLength = (uint)Marshal.SizeOf(saThread);
STARTUPINFO si = new STARTUPINFO();
si.cb = (uint)Marshal.SizeOf(si);
//if this member is NULL, the new process inherits the desktop
//and window station of its parent process. If this member is
//an empty string, the process does not inherit the desktop and
//window station of its parent process; instead, the system
//determines if a new desktop and window station need to be created.
//If the impersonated user already has a desktop, the system uses the
//existing desktop.
si.lpDesktop = @"WinSta0\Default"; //Modify as needed
si.dwFlags = STARTF_USESHOWWINDOW | STARTF_FORCEONFEEDBACK;
si.wShowWindow = SW_SHOW;
//Set other si properties as required.
result = CreateProcessAsUser(
token,
null,
cmdLine,
ref saProcess,
ref saThread,
false,
CREATE_UNICODE_ENVIRONMENT,
envBlock,
null,
ref si,
out pi);
if (result == false)
{
int error = Marshal.GetLastWin32Error();
string message = String.Format("CreateProcessAsUser Error: {0}", error);
Debug.WriteLine(message);
}
return result;
}
private static IntPtr GetPrimaryToken(int processId)
{
IntPtr token = IntPtr.Zero;
IntPtr primaryToken = IntPtr.Zero;
bool retVal = false;
Process p = null;
try
{
p = Process.GetProcessById(processId);
}
catch (ArgumentException)
{
string details = String.Format("ProcessID {0} Not Available", processId);
Debug.WriteLine(details);
throw;
}
//Gets impersonation token
retVal = OpenProcessToken(p.Handle, TOKEN_DUPLICATE, ref token);
if (retVal == true)
{
SECURITY_ATTRIBUTES sa = new SECURITY_ATTRIBUTES();
sa.nLength = (uint)Marshal.SizeOf(sa);
//Convert the impersonation token into Primary token
retVal = DuplicateTokenEx(
token,
TOKEN_ASSIGN_PRIMARY | TOKEN_DUPLICATE | TOKEN_QUERY,
ref sa,
(int)SECURITY_IMPERSONATION_LEVEL.SecurityIdentification,
(int)TOKEN_TYPE.TokenPrimary,
ref primaryToken);
//Close the Token that was previously opened.
CloseHandle(token);
if (retVal == false)
{
string message = String.Format("DuplicateTokenEx Error: {0}", Marshal.GetLastWin32Error());
Debug.WriteLine(message);
}
}
else
{
string message = String.Format("OpenProcessToken Error: {0}", Marshal.GetLastWin32Error());
Debug.WriteLine(message);
}
//We'll Close this token after it is used.
return primaryToken;
}
private static IntPtr GetEnvironmentBlock(IntPtr token)
{
IntPtr envBlock = IntPtr.Zero;
bool retVal = CreateEnvironmentBlock(ref envBlock, token, false);
if (retVal == false)
{
//Environment Block, things like common paths to My Documents etc.
//Will not be created if "false"
//It should not adversley affect CreateProcessAsUser.
string message = String.Format("CreateEnvironmentBlock Error: {0}", Marshal.GetLastWin32Error());
Debug.WriteLine(message);
}
return envBlock;
}
public static bool Launch(string appCmdLine /*,int processId*/)
{
bool ret = false;
//Either specify the processID explicitly
//Or try to get it from a process owned by the user.
//In this case assuming there is only one explorer.exe
Process[] ps = Process.GetProcessesByName("explorer");
int processId = -1;//=processId
if (ps.Length > 0)
{
processId = ps[0].Id;
}
if (processId > 1)
{
IntPtr token = GetPrimaryToken(processId);
if (token != IntPtr.Zero)
{
IntPtr envBlock = GetEnvironmentBlock(token);
ret = LaunchProcessAsUser(appCmdLine, token, envBlock);
if (envBlock != IntPtr.Zero)
DestroyEnvironmentBlock(envBlock);
CloseHandle(token);
}
}
return ret;
}
}
【讨论】：