I am currently writing a little bootstrap code for a service that can be run in the console. It essentially boils down to calling the OnStart() method instead of using the ServiceBase to start and stop the service (because it doesn't run the application if it isn't installed as a service and makes debugging a nightmare).
Right now I am using Debugger.IsAttached to determine if I should use ServiceBase.Run or [service].OnStart, but I know that isn't the best idea because some times end users want to run the service in a console (to see the output etc. realtime).
Any ideas on how I could determine if the Windows service controller started 'me', or if the user started 'me' in the console? Apparantly Environment.IsUserInteractive is not the answer. I thought about using commandline args, but that seems 'dirty'.
I could always see about a try-catch statement around ServiceBase.Run, but that seems dirty. Edit: Try catch doesn't work.
I have a solution: putting it up here for all the other interested stackers:
public void Run()
{
if (Debugger.IsAttached || Environment.GetCommandLineArgs().Contains<string>("-console"))
{
RunAllServices();
}
else
{
try
{
string temp = Console.Title;
ServiceBase.Run((ServiceBase[])ComponentsToRun);
}
catch
{
RunAllServices();
}
}
} // void Run
private void RunAllServices()
{
foreach (ConsoleService component in ComponentsToRun)
{
component.Start();
}
WaitForCTRLC();
foreach (ConsoleService component in ComponentsToRun)
{
component.Stop();
}
}
EDIT: There was another question on StackOverflow where the guy had problems with the Environment.CurrentDirectory being "C:\Windows\System32" looks like that may be the answer. I will test today.
Another workaround.. so can run as WinForm or as windows service
var backend = new Backend();
if (Environment.UserInteractive)
{
backend.OnStart();
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new Fronend(backend));
backend.OnStop();
}
else
{
var ServicesToRun = new ServiceBase[] {backend};
ServiceBase.Run(ServicesToRun);
}
I usually flag my Windows service as a console application which takes a command line parameter of "-console" to run using a console, otherwise it runs as a service. To debug you just set the command line parameters in the project options to "-console" and you're off!
This makes debugging nice and easy and means that the app functions as a service by default, which is what you'll want.
What works for me:
The class doing the actual service work is running in a separate thread.
This thread is started from within the OnStart() method, and stopped from OnStop().
The decision between service and console mode depends on Environment.UserInteractive
Sample code:
class MyService : ServiceBase
{
private static void Main()
{
if (Environment.UserInteractive)
{
startWorkerThread();
Console.WriteLine ("====== Press ENTER to stop threads ======");
Console.ReadLine();
stopWorkerThread() ;
Console.WriteLine ("====== Press ENTER to quit ======");
Console.ReadLine();
}
else
{
Run (this) ;
}
}
protected override void OnStart(string[] args)
{
startWorkerThread();
}
protected override void OnStop()
{
stopWorkerThread() ;
}
}
Like Ash, I write all actual processing code in a separate class library assembly, which was then referenced by the windows service executable, as well as a console app.
However, there are occasions when it is useful to know if the class library is running in the context of the service executable or the console app. The way I do this is to reflect on the base class of the hosting app. (Sorry for the VB, but I imagine that the following could be c#-ified fairly easily):
Public Class ExecutionContext
''' <summary>
''' Gets a value indicating whether the application is a windows service.
''' </summary>
''' <value>
''' <c>true</c> if this instance is service; otherwise, <c>false</c>.
''' </value>
Public Shared ReadOnly Property IsService() As Boolean
Get
' Determining whether or not the host application is a service is
' an expensive operation (it uses reflection), so we cache the
' result of the first call to this method so that we don't have to
' recalculate it every call.
' If we have not already determined whether or not the application
' is running as a service...
If IsNothing(_isService) Then
' Get details of the host assembly.
Dim entryAssembly As Reflection.Assembly = Reflection.Assembly.GetEntryAssembly
' Get the method that was called to enter the host assembly.
Dim entryPoint As System.Reflection.MethodInfo = entryAssembly.EntryPoint
' If the base type of the host assembly inherits from the
' "ServiceBase" class, it must be a windows service. We store
' the result ready for the next caller of this method.
_isService = (entryPoint.ReflectedType.BaseType.FullName = "System.ServiceProcess.ServiceBase")
End If
' Return the cached result.
Return CBool(_isService)
End Get
End Property
Private Shared _isService As Nullable(Of Boolean) = Nothing
#End Region
End Class
Jonathan, not exactly an answer to your question, but I've just finished writing a windows service and also noted the difficulty with debugging and testing.
Solved it by simply writing all actual processing code in a separate class library assembly, which was then referenced by the windows service executable, as well as a console app and a test harness.
Apart from basic timer logic, all more complex processing happened in the common assembly and could be tested/run on demand incredibly easily.
I have modified the ProjectInstaller to append the command-line argument parameter /service, when it is being installed as service:
static class Program
{
static void Main(string[] args)
{
if (Array.Exists(args, delegate(string arg) { return arg == "/install"; }))
{
System.Configuration.Install.TransactedInstaller ti = null;
ti = new System.Configuration.Install.TransactedInstaller();
ti.Installers.Add(new ProjectInstaller());
ti.Context = new System.Configuration.Install.InstallContext("", null);
string path = System.Reflection.Assembly.GetExecutingAssembly().Location;
ti.Context.Parameters["assemblypath"] = path;
ti.Install(new System.Collections.Hashtable());
return;
}
if (Array.Exists(args, delegate(string arg) { return arg == "/uninstall"; }))
{
System.Configuration.Install.TransactedInstaller ti = null;
ti = new System.Configuration.Install.TransactedInstaller();
ti.Installers.Add(new ProjectInstaller());
ti.Context = new System.Configuration.Install.InstallContext("", null);
string path = System.Reflection.Assembly.GetExecutingAssembly().Location;
ti.Context.Parameters["assemblypath"] = path;
ti.Uninstall(null);
return;
}
if (Array.Exists(args, delegate(string arg) { return arg == "/service"; }))
{
ServiceBase[] ServicesToRun;
ServicesToRun = new ServiceBase[] { new MyService() };
ServiceBase.Run(ServicesToRun);
}
else
{
Console.ReadKey();
}
}
}
The ProjectInstaller.cs is then modified to override a OnBeforeInstall() and OnBeforeUninstall()
[RunInstaller(true)]
public partial class ProjectInstaller : Installer
{
public ProjectInstaller()
{
InitializeComponent();
}
protected virtual string AppendPathParameter(string path, string parameter)
{
if (path.Length > 0 && path[0] != '"')
{
path = "\"" + path + "\"";
}
path += " " + parameter;
return path;
}
protected override void OnBeforeInstall(System.Collections.IDictionary savedState)
{
Context.Parameters["assemblypath"] = AppendPathParameter(Context.Parameters["assemblypath"], "/service");
base.OnBeforeInstall(savedState);
}
protected override void OnBeforeUninstall(System.Collections.IDictionary savedState)
{
Context.Parameters["assemblypath"] = AppendPathParameter(Context.Parameters["assemblypath"], "/service");
base.OnBeforeUninstall(savedState);
}
}
This thread is really old, but I thought I would throw my solution out there. Quite simply, to handle this type of situation, I built a "service harness" that is used in both the console and Windows service cases. As above, most of the logic is contained in a separate library, but this is more for testing and "linkability".
The attached code by no means represents the "best possible" way to solve this, just my own approach. Here, the service harness is called by the console app when in "console mode" and by the same application's "start service" logic when it is running as a service. By doing it this way, you can now call
ServiceHost.Instance.RunningAsAService (Boolean)
from anywhere in your code to check if the application is running as a service or simply as a console.
Here is the code:
public class ServiceHost
{
private static Logger log = LogManager.GetLogger(typeof(ServiceHost).Name);
private static ServiceHost mInstance = null;
private static object mSyncRoot = new object();
#region Singleton and Static Properties
public static ServiceHost Instance
{
get
{
if (mInstance == null)
{
lock (mSyncRoot)
{
if (mInstance == null)
{
mInstance = new ServiceHost();
}
}
}
return (mInstance);
}
}
public static Logger Log
{
get { return log; }
}
public static void Close()
{
lock (mSyncRoot)
{
if (mInstance.mEngine != null)
mInstance.mEngine.Dispose();
}
}
#endregion
private ReconciliationEngine mEngine;
private ServiceBase windowsServiceHost;
private UnhandledExceptionEventHandler threadExceptionHanlder = new UnhandledExceptionEventHandler(ThreadExceptionHandler);
public bool HostHealthy { get; private set; }
public bool RunningAsService {get; private set;}
private ServiceHost()
{
HostHealthy = false;
RunningAsService = false;
AppDomain.CurrentDomain.UnhandledException += threadExceptionHandler;
try
{
mEngine = new ReconciliationEngine();
HostHealthy = true;
}
catch (Exception ex)
{
log.FatalException("Could not initialize components.", ex);
}
}
public void StartService()
{
if (!HostHealthy)
throw new ApplicationException("Did not initialize components.");
try
{
mEngine.Start();
}
catch (Exception ex)
{
log.FatalException("Could not start service components.", ex);
HostHealthy = false;
}
}
public void StartService(ServiceBase serviceHost)
{
if (!HostHealthy)
throw new ApplicationException("Did not initialize components.");
if (serviceHost == null)
throw new ArgumentNullException("serviceHost");
windowsServiceHost = serviceHost;
RunningAsService = true;
try
{
mEngine.Start();
}
catch (Exception ex)
{
log.FatalException("Could not start service components.", ex);
HostHealthy = false;
}
}
public void RestartService()
{
if (!HostHealthy)
throw new ApplicationException("Did not initialize components.");
try
{
log.Info("Stopping service components...");
mEngine.Stop();
mEngine.Dispose();
log.Info("Starting service components...");
mEngine = new ReconciliationEngine();
mEngine.Start();
}
catch (Exception ex)
{
log.FatalException("Could not restart components.", ex);
HostHealthy = false;
}
}
public void StopService()
{
try
{
if (mEngine != null)
mEngine.Stop();
}
catch (Exception ex)
{
log.FatalException("Error stopping components.", ex);
HostHealthy = false;
}
finally
{
if (windowsServiceHost != null)
windowsServiceHost.Stop();
if (RunningAsService)
{
AppDomain.CurrentDomain.UnhandledException -= threadExceptionHanlder;
}
}
}
private void HandleExceptionBasedOnExecution(object ex)
{
if (RunningAsService)
{
windowsServiceHost.Stop();
}
else
{
throw (Exception)ex;
}
}
protected static void ThreadExceptionHandler(object sender, UnhandledExceptionEventArgs e)
{
log.FatalException("Unexpected error occurred. System is shutting down.", (Exception)e.ExceptionObject);
ServiceHost.Instance.HandleExceptionBasedOnExecution((Exception)e.ExceptionObject);
}
}
All you need to do here is replace that ominous looking ReconcilationEngine reference with whatever method is boostrapping your logic. Then in your application, use the ServiceHost.Instance.Start() and ServiceHost.Instance.Stop() methods whether you are running in console mode or as a service.
Maybe checking if the process parent is C:\Windows\system32\services.exe.
The only way I've found to achieve this, is to check if a console is attached to the process in the first place, by accessing any Console object property (e.g. Title) inside a try/catch block.
If the service is started by the SCM, there is no console, and accessing the property will throw a System.IO.IOError.
However, since this feels a bit too much like relying on an implementation-specific detail (what if the SCM on some platforms or someday decides to provide a console to the processes it starts?), I always use a command line switch (-console) in production apps...
Here is a translation of chksr's answer to .NET, and avoiding the bug that fails to recognize interactive services:
using System.Security.Principal;
var wi = WindowsIdentity.GetCurrent();
var wp = new WindowsPrincipal(wi);
var serviceSid = new SecurityIdentifier(WellKnownSidType.ServiceSid, null);
var localSystemSid = new SecurityIdentifier(WellKnownSidType.LocalSystemSid, null);
var interactiveSid = new SecurityIdentifier(WellKnownSidType.InteractiveSid, null);
// maybe check LocalServiceSid, and NetworkServiceSid also
bool isServiceRunningAsUser = wp.IsInRole(serviceSid);
bool isSystem = wp.IsInRole(localSystemSid);
bool isInteractive = wp.IsInRole(interactiveSid);
bool isAnyService = isServiceRunningAsUser || isSystem || !isInteractive;
This is a bit of a self-plug, but I've got a little app that will load up your service types in your app via reflection and execute them that way. I include the source code, so you could change it slightly to display standard output.
No code changes needed to use this solution. I have a Debugger.IsAttached type of solution as well that is generic enough to be used with any service. Link is in this article:
.NET Windows Service Runner
Well there's some very old code (about 20 years or so, not from me but found in the wild, wild web, and in C not C#) that should give you an idea how to do the job:
enum enEnvironmentType
{
ENVTYPE_UNKNOWN,
ENVTYPE_STANDARD,
ENVTYPE_SERVICE_WITH_INTERACTION,
ENVTYPE_SERVICE_WITHOUT_INTERACTION,
ENVTYPE_IIS_ASP,
};
enEnvironmentType GetEnvironmentType(void)
{
HANDLE hProcessToken = NULL;
DWORD groupLength = 300;
PTOKEN_GROUPS groupInfo = NULL;
SID_IDENTIFIER_AUTHORITY siaNt = SECURITY_NT_AUTHORITY;
PSID pInteractiveSid = NULL;
PSID pServiceSid = NULL;
DWORD dwRet = NO_ERROR;
DWORD ndx;
BOOL m_isInteractive = FALSE;
BOOL m_isService = FALSE;
// open the token
if (!::OpenProcessToken(::GetCurrentProcess(),TOKEN_QUERY,&hProcessToken))
{
dwRet = ::GetLastError();
goto closedown;
}
// allocate a buffer of default size
groupInfo = (PTOKEN_GROUPS)::LocalAlloc(0, groupLength);
if (groupInfo == NULL)
{
dwRet = ::GetLastError();
goto closedown;
}
// try to get the info
if (!::GetTokenInformation(hProcessToken, TokenGroups,
groupInfo, groupLength, &groupLength))
{
// if buffer was too small, allocate to proper size, otherwise error
if (::GetLastError() != ERROR_INSUFFICIENT_BUFFER)
{
dwRet = ::GetLastError();
goto closedown;
}
::LocalFree(groupInfo);
groupInfo = (PTOKEN_GROUPS)::LocalAlloc(0, groupLength);
if (groupInfo == NULL)
{
dwRet = ::GetLastError();
goto closedown;
}
if (!GetTokenInformation(hProcessToken, TokenGroups,
groupInfo, groupLength, &groupLength))
{
dwRet = ::GetLastError();
goto closedown;
}
}
//
// We now know the groups associated with this token. We want
// to look to see if the interactive group is active in the
// token, and if so, we know that this is an interactive process.
//
// We also look for the "service" SID, and if it's present,
// we know we're a service.
//
// The service SID will be present iff the service is running in a
// user account (and was invoked by the service controller).
//
// create comparison sids
if (!AllocateAndInitializeSid(&siaNt,
1,
SECURITY_INTERACTIVE_RID,
0, 0, 0, 0, 0, 0, 0,
&pInteractiveSid))
{
dwRet = ::GetLastError();
goto closedown;
}
if (!AllocateAndInitializeSid(&siaNt,
1,
SECURITY_SERVICE_RID,
0, 0, 0, 0, 0, 0, 0,
&pServiceSid))
{
dwRet = ::GetLastError();
goto closedown;
}
// try to match sids
for (ndx = 0; ndx < groupInfo->GroupCount ; ndx += 1)
{
SID_AND_ATTRIBUTES sanda = groupInfo->Groups[ndx];
PSID pSid = sanda.Sid;
//
// Check to see if the group we're looking at is one of
// the two groups we're interested in.
//
if (::EqualSid(pSid, pInteractiveSid))
{
//
// This process has the Interactive SID in its
// token. This means that the process is running as
// a console process
//
m_isInteractive = TRUE;
m_isService = FALSE;
break;
}
else if (::EqualSid(pSid, pServiceSid))
{
//
// This process has the Service SID in its
// token. This means that the process is running as
// a service running in a user account ( not local system ).
//
m_isService = TRUE;
m_isInteractive = FALSE;
break;
}
}
if ( !( m_isService || m_isInteractive ) )
{
//
// Neither Interactive or Service was present in the current
// users token, This implies that the process is running as
// a service, most likely running as LocalSystem.
//
m_isService = TRUE;
}
closedown:
if ( pServiceSid )
::FreeSid( pServiceSid );
if ( pInteractiveSid )
::FreeSid( pInteractiveSid );
if ( groupInfo )
::LocalFree( groupInfo );
if ( hProcessToken )
::CloseHandle( hProcessToken );
if (dwRet == NO_ERROR)
{
if (m_isService)
return(m_isInteractive ? ENVTYPE_SERVICE_WITH_INTERACTION : ENVTYPE_SERVICE_WITHOUT_INTERACTION);
return(ENVTYPE_STANDARD);
}
else
return(ENVTYPE_UNKNOWN);
}
Seems I am bit late to the party, but interesting difference when run as a service is that at start current folder points to system directory (C:\windows\system32 by default). Its hardly unlikely user app will start from the system folder in any real life situation.
So, I use following trick (c#):
protected static bool IsRunAsService()
{
string CurDir = Directory.GetCurrentDirectory();
if (CurDir.Equals(Environment.SystemDirectory, StringComparison.CurrentCultureIgnoreCase))
{
return true;
}
return (false);
}
For future extension, additional check make be done for System.Environment.UserInteractive == false (but I do not know how it correlates with 'Allow service to interact with desktop' service settings).
You may also check window session by System.Diagnostics.Process.GetCurrentProcess().SessionId == 0 (I do not know how it correlates with 'Allow service to interact with desktop' service settings as well).
If you write portable code (say, with .NetCore) you may also check Environment.OSVersion.Platform to ensure that you are on windows first.
I am developing a tray icon based application in C++ CLI. I am using Mutex to ensure single instance of my application running at a time. But each time a new instance starts, the current instance's window should go active.
I am sending a message to the window using PostMessage(Pinvoke). But after 3 or 4 successive run, my application crashes.
Any ideas why that happen. please help!!
The code I have written in the main() function is,
Mutex ^mutex = gcnew Mutex(true, "{8F6F0AC4-B9A1-45fd-A8CF-72F04E6BDE8F}");
if (mutex->WaitOne(TimeSpan::Zero, true))
{
// New Instance. Proceed......................
}
else// An instance is already running. Activate it and return
{
// send our Win32 message to make the currently running instance
// jump on top of all the other windows
try
{
HWND hWindow = FindWindow( nullptr, "MyWindow" );
if(hWindow)
PostMessage(hWindow, WM_ACTIVATE_APP, nullptr,nullptr);
}
catch(Exception^ Ex)
{
}
return -1;
}
Thanks & Regards,
Rohini
Try this instead of PostMessage():
ShowWindowAsync(hWindow, 1); // SW_SHOWNORMAL
SetForegroundWindow(hWindow);
This question already has answers here:
What is the correct way to create a single-instance WPF application?
(39 answers)
Closed 6 years ago.
I have a application but currently it is not a singleton application.
I like to make it singleton application so that its another instance does not exit at the run time .
If this can be done please reply with some sample codes .
I think the following codes will be helpful for you.
Here is the related link:
http://geekswithblogs.net/chrisfalter/archive/2008/06/06/how-to-create-a-windows-form-singleton.aspx
static class Program
{
/// <summary>
/// The main entry point for the application.
/// </summary>
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
/*====================================================
*
* Add codes here to set the Winform as Singleton
*
* ==================================================*/
bool mutexIsAvailable = false;
Mutex mutex = null;
try
{
mutex = new Mutex(true, "SampleOfSingletonWinForm.Singleton");
mutexIsAvailable = mutex.WaitOne(1, false); // Wait only 1 ms
}
catch (AbandonedMutexException)
{
// don't worry about the abandonment;
// the mutex only guards app instantiation
mutexIsAvailable = true;
}
if (mutexIsAvailable)
{
try
{
Application.Run(new SampleOfSingletonWinForm());
}
finally
{
mutex.ReleaseMutex();
}
}
//Application.Run(new SampleOfSingletonWinForm());
}
}
Here are some good sample applications. Below is one possible way.
public static Process RunningInstance()
{
Process current = Process.GetCurrentProcess();
Process[] processes = Process.GetProcessesByName (current.ProcessName);
//Loop through the running processes in with the same name
foreach (Process process in processes)
{
//Ignore the current process
if (process.Id != current.Id)
{
//Make sure that the process is running from the exe file.
if (Assembly.GetExecutingAssembly().Location.
Replace("/", "\\") == current.MainModule.FileName)
{
//Return the other process instance.
return process;
}
}
}
//No other instance was found, return null.
return null;
}
if (MainForm.RunningInstance() != null)
{
MessageBox.Show("Duplicate Instance");
//TODO:
//Your application logic for duplicate
//instances would go here.
}
Many other possible ways. See the examples for alternatives.
First one.
Second One.
Third One.
The approach I know of is the following. The program must attempt to open a named mutex. If that mutex existed, then exit, otherwise, create the mutex. But this seems to contradict your condition that "its another instance does not exit at the run time". Anyway, maybe this too was helpful
I use a Console Application in Windows Mobile to handle incoming message interception. In the same console application i accept parameters (string args[]) which based on the parameters, register the message interceptor.
InterceptorType is a enum
static void Main(string[] args)
{
if (args[0] == "Location")
{
addInterception(InterceptorType.Location, args[1],args[2]);
}
}
private static void addInterception(InterceptorType type, string Location, string Number )
{
if (type == InterceptorType.Location)
{
using (MessageInterceptor interceptor = new MessageInterceptor(InterceptionAction.NotifyAndDelete, false))
{
interceptor.MessageCondition = new MessageCondition(MessageProperty.Sender, MessagePropertyComparisonType.Contains, Number, false);
string myAppPath = Assembly.GetExecutingAssembly().GetName().CodeBase;
interceptor.EnableApplicationLauncher("Location", myAppPath);
interceptor.MessageReceived += new MessageInterceptorEventHandler(interceptor_MessageReceived);
}
}
}
static void interceptor_MessageReceived(object sender, MessageInterceptorEventArgs e)
{
//Do something
}
I made this a console application because i want it keep running in the background and intercept incoming messages.
This works fine for the first time. But the problem is that I have to keep calling the addInterception method to add subsequent interception rules. This makes the console application start again and again for each time i add a rule. How do i make this run only once and add more message interceptor rules?
Since you already have a method in place to call the command prompt once, update your logic with some simple looping so you can pass N commands.
EDIT: I wrote it a fully compileable example to show you exactly what I am talking about. Note how the child process can be called any number of times without re-launching. This is not just a simple command line launch with arguments being passed because that idea will lead to X processes which is exactly what you do not want.
PARENT PROCESS: (The one with System.Diagnostics.Process)
/// <summary>
/// This is the calling application. The one where u currently have System.Diagnostics.Process
/// </summary>
class Program
{
static void Main(string[] args)
{
System.Diagnostics.Process p = new Process();
p.StartInfo.CreateNoWindow = false;
p.StartInfo.UseShellExecute = false;
p.StartInfo.FileName = #"C:\AppfolderThing\ConsoleApplication1.exe";
p.StartInfo.RedirectStandardError = true;
p.StartInfo.RedirectStandardInput = true;
p.StartInfo.RedirectStandardOutput = true;
p.Start();
p.OutputDataReceived += delegate(object sender, DataReceivedEventArgs e)
{
Console.WriteLine("Output received from application: {0}", e.Data);
};
p.ErrorDataReceived += delegate(object sender, DataReceivedEventArgs e)
{
Console.WriteLine("Output received from application: {0}", e.Data);
};
p.BeginErrorReadLine();
p.BeginOutputReadLine();
StreamWriter inputStream = p.StandardInput;
inputStream.WriteLine(1);
inputStream.WriteLine(2);
inputStream.WriteLine(-1);//tell it to exit
p.WaitForExit();
}
}
CHILD PROCESS:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace ConsoleApplication3
{
enum InterceptorType
{
foo,
bar,
zee,
brah
}
/// <summary>
/// This is the child process called by System.Diagnostics.Process
/// </summary>
class Program
{
public static void Main()
{
while (true)
{
int command = int.Parse(Console.ReadLine());
if (command == -1)
Environment.Exit(0);
else
addInterception((InterceptorType)command, "some location", "0");
}
}
private static void addInterception(InterceptorType type, string Location, string Number)
{
switch (type)
{
case InterceptorType.foo: Console.WriteLine("bind foo"); break;
case InterceptorType.bar: Console.WriteLine("bind bar"); break;
default: Console.WriteLine("default bind zee"); break;
}
}
static void interceptor_MessageReceived(object sender, EventArgs e)
{
//Do something
}
}
}
Note that codeplex has a managed service library.
EDIT
It seems that people are misunterstanding your question (or I am) so here's some clarification on how I'm seeing the problem.
You have an console app that takes in command-line parameters. These parameters are used for something (the what is irrelevant actually). You want to be able to add parameters after the app is already running by calling the app with new command line args.
What is happening is that when you call the app any time after teh first, a new instance of the process starts up instead of the command-line arguments going to the existing, already running application.
END EDIT
The solution is fairly straightforward and requires two pieces.
You need a named mutex. For whatever (poor) reason, the CF doesn't expose a version of a mutex that takes a name, so you have to P/Invoke CreateMutex or use a library (like the SDF) that already has it. Your app needs to create the mutex at startup and check to see if it already exists. if it doesn't you're the first running instance and run as normal. If the mutex exists, you need to pass your command line args to the one that is already running via a P2P queue then simply exits.
After checking the mutex, the first instance spawns a worker thread. This thread listens on a P2P queue for messages. When they come in, you handle them.
I have a .NET application that I only allow to run a single process at a time of, however that app is used on Citrix boxes from time to time, and as such, can be run by multiple users on the same machine.
I want to check and make sure that the application is only running once per user session, because right now if user A is running the app, then user B gets the "App already in use" message, and should not.
This is what I have now that checks for the running process:
Process[] p = Process.GetProcessesByName(Process.GetCurrentProcess().ProcessName);
if (p.Length > 1)
{
#if !DEBUG
allowedToOpen &= false;
errorMessage +=
string.Format("{0} is already running.{1}", Constants.AssemblyTitle, Environment.NewLine);
#endif
}
EDIT: Improved the answer according to this cw question ...
You can use a mutex for checking wether the app already runs:
using( var mutex = new Mutex( false, AppGuid ) )
{
try
{
try
{
if( !mutex.WaitOne( 0, false ) )
{
MessageBox.Show( "Another instance is already running." );
return;
}
}
catch( AbandonedMutexException )
{
// Log the fact the mutex was abandoned in another process,
// it will still get aquired
}
Application.Run(new Form1());
}
finally
{
mutex.ReleaseMutex();
}
}
Important is the AppGuid - you could make it depend on the user.
Maybe you like to read this article: the misunderstood mutex
As tanascius already say, you can use the Mutex.
On a server that is running Terminal Services, a named system mutex can have two levels of visibility. If its name begins with the prefix "Global\", the mutex is visible in all terminal server sessions. If its name begins with the prefix "Local\", the mutex is visible only in the terminal server session where it was created.
Source: msdn, Mutex Class
Just stating the obvious - although Mutex is usually considered better solution, you can still solve the single-instance-per-session issue without Mutex - just test the SessionId as well.
private static bool ApplicationIsAlreadyRunning()
{
var currentProcess = Process.GetCurrentProcess();
var processes = Process.GetProcessesByName(currentProcess.ProcessName);
// test if there's another process running in current session.
var intTotalRunningInCurrentSession = processes.Count(prc => prc.SessionId == currentProcess.SessionId);
return intTotalRunningInCurrentSession > 1;
}
Source (no Linq)
If Form1 launches non-background threads, and that Form1 exits, you've got a problem: the mutex is released but the process is still there. Something along the lines below is better IMHO:
static class Program {
private static Mutex mutex;
/// <summary>
/// The main entry point for the application.
/// </summary>
[STAThread]
static void Main() {
bool createdNew = true;
mutex = new Mutex(true, #"Global\Test", out createdNew);
if (createdNew) {
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new Form1());
}
else {
MessageBox.Show(
"Application is already running",
"Error",
MessageBoxButtons.OK,
MessageBoxIcon.Error
);
}
}
}
The mutex won't be released as long as the primary application domain is still up. And that will be around as long as the application is running.