I just implemented this code that is guarding the Single Instance of the Application, in order to not run the application twice.
Now I am wondering how I can show the original Application process that is already running.
Here is my code in the program class:
static class Program
{
[STAThread]
static void Main()
{
const string appName = "MyappName";
bool createdNew;
mutex = new Mutex(true, appName, out createdNew);
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Form form = new Form1();
if (!createdNew)
{
form.Show(); <<=========================== NOT WORKING
form.Visible = true; <<===================== None
form.TopMost = true; <<===================== of
form.BringToFront(); <<===================== these working!
form.WindowState = FormWindowState.Maximized;
return;
}
Application.Run(form);
} private static Mutex mutex = null;
}
I propose you a different method, using a combination of the System.Threading.Mutex class and UIAutomation AutomationElement class.
A Mutex can be, as you already know, a simple string. You can assign an application a Mutex in the form of a GUID, but it can be anything else.
Let's assume this is the current Application Mutex:
string ApplicationMutex = "BcFFcd23-3456-6543-Fc44abcd1234";
//Or
string ApplicationMutex = "Global\BcFFcd23-3456-6543-Fc44abcd1234";
Note:
Use the "Global\" Prefix to define the scope of the Mutex. If no prefix is specified, the "Local\" prefix is assumed and used instead. This will prevent a single instance of the process when multiple desktops are active or Terminal Services is running on the server.
If we want to verify whether another running Process has already registered the same Mutex, we try to register our Mutex and if it fails, another instance of our Application is already running.
We let the user know that the Application supports only a single instance, then switch to the running process, showing its interface and finally exit the duplicate Application, disposing of the Mutex.
The method to activate a previous instance of the Application may vary based on the type of the Application, but only some details change.
We can use Process..GetProcesses() to retrieve a list of the running processes and verify if one of them has the same details as ours.
Here, you have a windowed Application (it has an UI), so it's already possible to filter the list, excluding those processes that do not have a MainWindowHandle.
Process[] windowedProcesses =
Process.GetProcesses().Where(p => p.MainWindowHandle != IntPtr.Zero).ToArray();
To identify the right one, we could test if the Process.ProcessName is the same.
But this name is tied to the executable name. If the file name changes (someone changes it for some reason), we will never identify the Process this way.
One possible way to identify the right Process is to test the Process.MainModule.FileVersionInfo.ProductName and check whether it's the same.
When found, it's possible to bring the original Application to front with an AutomationElement created using the MainWindowHandle of the identified Process.
The AutomationElement can automate different Patterns (sort of controls that provide automation functionalities for UI elements).
A WindowPattern allows to control a window-base control (the Platform is irrelevant, could be a WinForms' Form or a WPF's Window).
AutomationElement element = AutomationElement.FromHandle(process.MainWindowHandle);
WindowPattern wPattern = element.GetCurrentPattern(WindowPattern.Pattern) as WindowPattern;
wPattern.SetWindowVisualState(WindowVisualState.Normal);
To use the UIAutomation functionalities, you have to add these refereneces in your Project:
- UIAutomationClient
- UIAutomationTypes
UPDATE:
Since the Application's Form might be hidden, Process.GetProcesses() will not find it's Window handle, thus AutomationElement.FromHandle() cannot be used to identify the Form Window.
A possible workaround, without dismissing the UIAutomation "pattern", is to register an Automation event, using Automation.AddAutomationEventHandler, which allows to receive a notification when an UI Automation events occurs, such as a new Window is about to be shown (a Program is run).
The event is registerd only if the Application needs to run as Single Instance. When the event is raised, the new Process AutomationElement Name (the Windows Title Text) is compared to the current and, if it's the same, the hidden Form will un-hide and show itself in Normal state.
As a fail-safe measure, we present an information MessageBox. The MessageBox caption has the same caption as the Application MainForm.
(Tested with a Form with its WindowsState set to Minimized and its Visible property set to false).
After the orginal Process has been brought to front, we just neeed to close the current thread and release the resources we created (mainly the Mutex, in this case).
using System;
using System.Diagnostics;
using System.Linq;
using System.Threading;
using System.Windows.Automation;
using System.Windows.Forms;
static class Program
{
static Mutex mutex = null;
[STAThread]
static void Main()
{
Application.ThreadExit += ThreadOnExit;
string applicationMutex = #"Global\BcFFcd23-3456-6543-Fc44abcd1234";
mutex = new Mutex(true, applicationMutex);
bool singleInstance = mutex.WaitOne(0, false);
if (!singleInstance)
{
string appProductName = Process.GetCurrentProcess().MainModule.FileVersionInfo.ProductName;
Process[] windowedProcesses =
Process.GetProcesses().Where(p => p.MainWindowHandle != IntPtr.Zero).ToArray();
foreach (Process process in windowedProcesses.Where(p => p.MainModule.FileVersionInfo.ProductName == appProductName))
{
if (process.Id != Process.GetCurrentProcess().Id)
{
AutomationElement wElement = AutomationElement.FromHandle(process.MainWindowHandle);
if (wElement.Current.IsOffscreen)
{
WindowPattern wPattern = wElement.GetCurrentPattern(WindowPattern.Pattern) as WindowPattern;
#if DEBUG
WindowInteractionState state = wPattern.Current.WindowInteractionState;
Debug.Assert(!(state == WindowInteractionState.NotResponding), "The application is not responding");
Debug.Assert(!(state == WindowInteractionState.BlockedByModalWindow), "Main Window blocked by a Modal Window");
#endif
wPattern.SetWindowVisualState(WindowVisualState.Normal);
break;
}
}
}
Thread.Sleep(200);
MessageBox.Show("Application already running", "MyApplicationName",
MessageBoxButtons.OK, MessageBoxIcon.Information,
MessageBoxDefaultButton.Button1, MessageBoxOptions.ServiceNotification);
}
if (SingleInstance) {
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new MyAppMainForm());
}
else {
Application.ExitThread();
}
}
private static void ThreadOnExit(object s, EventArgs e)
{
mutex.Dispose();
Application.ThreadExit -= ThreadOnExit;
Application.Exit();
}
}
In the Application MainForm constructor:
(this is used in case the Application's Main Window is hidden when a new instance is run, hence the procedure in Program.cs cannot find its handle)
public partial class MyAppMainForm : Form
{
public MyAppMainForm()
{
InitializeComponent();
Automation.AddAutomationEventHandler(WindowPattern.WindowOpenedEvent,
AutomationElement.RootElement,
TreeScope.Subtree, (uiElm, evt) =>
{
AutomationElement element = uiElm as AutomationElement;
string windowText = element.Current.Name;
if (element.Current.ProcessId != Process.GetCurrentProcess().Id && windowText == this.Text)
{
this.BeginInvoke(new MethodInvoker(() =>
{
this.WindowState = FormWindowState.Normal;
this.Show();
}));
}
});
}
}
Run Only One time :
static class Program
{
[STAThread]
static void Main()
{
bool createdNew = true;
using (Mutex mutex = new Mutex(true, "samplename", out createdNew))
{
if (createdNew)
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.ThreadException += new ThreadExceptionEventHandler(Application_ThreadException);
AppDomain.CurrentDomain.UnhandledException += new UnhandledExceptionEventHandler(CurrentDomain_UnhandledException);
Application.Run(new Form1());
}
else
{
ProcessUtils.SetFocusToPreviousInstance("samplename");
}
}
}
private static void CurrentDomain_UnhandledException(object sender, UnhandledExceptionEventArgs e)
{
}
private static void Application_ThreadException(object sender, ThreadExceptionEventArgs e)
{
}
}
ProcessUtils :
public static class ProcessUtils
{
[DllImport("user32.dll", SetLastError = true)]
static extern IntPtr FindWindow(string lpClassName, string lpWindowName);
[DllImport("user32.dll")]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool SetForegroundWindow(IntPtr hWnd);
[DllImport("user32.dll")]
static extern bool IsIconic(IntPtr hWnd);
[DllImport("user32.dll")]
static extern bool ShowWindow(IntPtr hWnd, int nCmdShow);
const int SW_RESTORE = 9;
[DllImport("user32.dll")]
static extern IntPtr GetLastActivePopup(IntPtr hWnd);
[DllImport("user32.dll")]
static extern bool IsWindowEnabled(IntPtr hWnd);
public static void SetFocusToPreviousInstance(string windowCaption)
{
IntPtr hWnd = FindWindow(null, windowCaption);
if (hWnd != null)
{
IntPtr hPopupWnd = GetLastActivePopup(hWnd);
if (hPopupWnd != null && IsWindowEnabled(hPopupWnd))
{
hWnd = hPopupWnd;
}
SetForegroundWindow(hWnd);
if (IsIconic(hWnd))
{
ShowWindow(hWnd, SW_RESTORE);
}
}
}
}
Normal Run :
static class Program
{
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new Form1());
}
}
If you are still looking for an answer. There is a good example here that
uses windows messages to restore the previous instance. It work even if the first instance is minimized contrary to FindWindow witch does not work in that case.
I use this code to check whether my program is already open:
string RunningProcess = System.Diagnostics.Process.GetCurrentProcess().ProcessName;
System.Diagnostics.Process[] processes = System.Diagnostics.Process.GetProcessesByName(RunningProcess);
if (processes.Length > 1)
{ return true; }
It would, if the program is open, bring it to the floor and show it. How can I do? Thank you.
You have to import the following method:
[DllImport("user32.dll")]
static extern bool ShowWindow(IntPtr hwnd, int nCmdShow);
Then you can call this method this way:
ShowWindow(process.MainWindowHandle, 0);//Hide
ShowWindow(process.MainWindowHandle, 1);//Show
NOTE: The window can just be shown if it is minimized. It won't show it if it is in the background of an other window.
If you want to show a window that is in the background of an other one you have to import this method:
[DllImport("user32.dll")]
static extern bool SetForegroundWindow(IntPtr hWnd);
Then call it in the same way as ShowWindow:
SetForegroundWindow(process.MainWindowHandle);
NOTE: You can just set the foreground window if it is not minimized.
You can also combine both methods with IsIconic to call the right method:
[DllImport("user32.dll")]
static extern bool IsIconic(IntPtr hWnd);//Returns false if the window is minimized
The full code to show the mainwindow:
static void GotoProcess(Process process)
{
if (IsIconic(process.MainWindowHandle))
{
ShowWindow(process.MainWindowHandle, 1);
}
else
{
SetForegroundWindow(process.MainWindowHandle);
}
}
This question already has answers here:
Show/Hide the console window of a C# console application
(9 answers)
Closed 7 years ago.
I have an application that was using the console, but I changed all the code to write to a file instead of the console. I would now like the console to stop appearing when I run the application. How do I do this? I do not know what is opening the console in the first place, even though nothing is being written to it in the code.
I have looked in the applications references and cannot find System.Console being referenced. I though disabling that would fix it or point me in the right direction with errors. I am not sure where else to look.
All the other things I found online talk about making the console hidden. I would like it to not appear in the first place.
Go to the Application Properties and change Output Type from Console Application to Windows Application.
Or you can do it using a code below
using System.Runtime.InteropServices;
[DllImport("kernel32.dll")]
static extern IntPtr GetConsoleWindow();
[DllImport("user32.dll")]
static extern bool ShowWindow(IntPtr hWnd, int nCmdShow);
And in main
const int SW_HIDE = 0;
const int SW_SHOW = 5;
var handle = GetConsoleWindow();
ShowWindow(handle, SW_HIDE); // To hide
ShowWindow(handle, SW_SHOW); // To show
Also, you can run you application as a service. In order to do this you should create a service - File->New Project->Visual C#->Windows->Windows Service. Then create a public method StartWork() and add all you logic there. And call this method in OnStart().
protected override void OnStart(string[] args)
{
try
{
this.StartJobs();
}
catch (Exception ex)
{
// catching exception
}
}
public void StartWork()
{
// all the logic here
}
In main you should create this service and use System.ServiceProcess.ServiceBase.Run() to run it as service or call StartWork() to run it as console application.
static void Main(string[] args)
{
TestService = new TestService ();
#if DEBUG
TestService.StartWork()();
#else
System.ServiceProcess.ServiceBase.Run(TestService );
#endif
}
I want to create a software like a virtualkeyboard, you have a AlwaysTop Window and use this to put some data on another process/windows. In this case I will record all data on clipboard and compare if this data is compatible with a pattern (A### is the patern and A123 is compatible with the patern), if yes the application will put it in a listbox and the user can paste it on another process/windows (already open) clicking on item on list.
My question is about how to put this information on the last application/process used, I already started a prototype of code but the line indicated is wrong, on my code it's the currentprocess and need to be the last used before click on my form.
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
[DllImport("user32.dll")]
static extern IntPtr SetForegroundWindow(IntPtr hWnd);
[DllImport("user32.dll")]
internal static extern bool ShowWindow(IntPtr hWnd, int nCmdShow);
[DllImport("User32.dll")]
static extern uint GetWindowThreadProcessId(IntPtr hWnd, out uint lpdwProcessId);
private void button2_Click(object sender, EventArgs e)
{
Process currentProcess = Process.GetCurrentProcess(); //this line is wrong
IntPtr hWnd = currentProcess.MainWindowHandle; //this line is wrong
if (hWnd != IntPtr.Zero)
{
SetForegroundWindow(hWnd);
ShowWindow(hWnd, 9);
SendKeys.Send("A123");
}
}
}
}
I get on simple solution, instead of get the process I just send the combination ALT+TAB and work for all cases that I need. Below the solution if anyone need in the future:
string old_clipboard = Clipboard.GetText();
Clipboard.SetText("A123");
SendKeys.SendWait("%{Tab}");
SendKeys.SendWait("^V");
Thread.Sleep(100);
Clipboard.SetText(old_clipboard);
Ps.: I put one delay because the SendWait works only on caller windows, as the target of ^V is another process it´s don´t work well.
Best regards. =)
I am developing a software for a blind individual in C# .NET.
The software works only with the keyboard and voice to speech.
When the computer starts the program is in the start up menu, but for some reason the program is activated not in focus therefore it does not work properly unless the focus is re transferred to it.
I found a way to hook keyboard keys even when the software is not in focus but I don't see that as a solution.
I want a way to do one or more of the following:
Make sure the program loads on start up and is in focus.
Maintain focus on the program (this computer will be run only using this program).
Find a keyboard shortcut, preferably one key only (not Alt + Tab) to return focus to the program.
There are many ways you can solve this ie you can run on startup console app that will run and focus your program:
[STAThread]
static void Main(string[] args)
{
System.Diagnostics.Process myProcess = new System.Diagnostics.Process();
myProcess.StartInfo.FileName = "calc";
myProcess.Start();
IntPtr hWnd = myProcess.Handle;
SetFocus(new HandleRef(null, hWnd));
}
[DllImport("user32.dll", CharSet = CharSet.Auto, ExactSpelling = true)]
public static extern IntPtr SetFocus(HandleRef hWnd);
You can host a windows service application and using timer check if your app is alive and is focused or you can use hotkeys to bring it back focused: http://www.codeproject.com/KB/miscctrl/ashsimplehotkeys.aspx
Edited
this is console application, that will keep your app alive and focused (tested). i need to find walkaround for windows service becouse since vista something changed and form is invisible when stared from service :P
static Process myProcess;
[STAThread]
static void Main(string[] args)
{
for (int i = 0; i < 10000; i++)
{
//count how many procesess with this name are active if more than zero its still alive
Process[] proc = Process.GetProcessesByName("myprog");
if (proc.Length > 0)
{
//its alive check if it has focus
if (proc[0].MainWindowHandle != GetForegroundWindow())
{
SetFocus(proc[0].MainWindowHandle);
}
}
//no process start new one and focus on it
else
{
myProcess = new Process();
myProcess.StartInfo.FileName = "C:\\aa\\myprog.exe";
myProcess.Start();
SetFocus(myProcess.Handle);
}
Thread.Sleep(1000);
}
}
private static void SetFocus(IntPtr handle)
{
SwitchToThisWindow(handle, true);
}
[DllImport("user32.dll")]
static extern IntPtr GetForegroundWindow();
[DllImport("user32.dll", SetLastError = true)]
public static extern void SwitchToThisWindow(IntPtr hWnd, bool fAltTab);