start single instance project

Question

I want that my application run only single instance, I used for that the code under pasted under, but It gives me an error :

Error   1   'MYAPP.App' does not implement interface member 
            'Microsoft.Shell.ISingleInstanceApp.SignalExternalCommandLineArgs
             (System.Collections.Generic.IList<string>)'
            C:\Users\moataz\Desktop\MYAPP 26-06-2013\MYAPP\App.xaml.cs

http://www.codeproject.com/Articles/84270/WPF-Single-Instance-Application

Your question is completely different to your title, and your not implementing an interface correctly, right click the interface at top of your class and then click on implement — Sayse, Jul 20 '13 at 09:10
Have you checked this SOF post ? It worked for me. http://stackoverflow.com/questions/646480/is-using-a-mutex-to-prevent-multipule-instances-of-the-same-program-from-running/646500 — Nitesh, Jul 20 '13 at 09:11
@tp1 You should use Mutex for that. See my answer below on implementation. — Ehsan, Jul 20 '13 at 09:51

score 3 · Answer 1 · edited May 23 '17 at 12:03

3

As stated in the article you posted -

Step 3: Have your application class implement ISingleInstanceApp (defined in SingleInstance.cs).

So, you need to implement this interface for your App.xaml.cs.

Though, personally i would suggest you to use Mutex to achieve single instance application. Detials can be found here.

edited May 23 '17 at 12:03

Community

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answered Jul 20 '13 at 09:12

Rohit Vats

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score 0 · Answer 2 · answered Jul 20 '13 at 09:06

0

Why don't you check from running processes in system. If your application name is in running processes , don't run another instance of it your application. Instead bring that instance to view.

answered Jul 20 '13 at 09:06

Nikhil Agrawal

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score 0 · Answer 3 · answered Jul 20 '13 at 09:17

0

Add below piece of code in your App.xaml.cs and see if it works for you.

static EventWaitHandle s_event;
bool created;  

App()
{
    s_event = new EventWaitHandle (false, EventResetMode.ManualReset, "my program#startup", out created) ;
    if (!created)
    {
        if (MessageBoxResult.OK == MessageBox.Show("Only 1 instance of this application can run at a time", "Error", MessageBoxButton.OK))
            App.Current.Shutdown();
    }
}

answered Jul 20 '13 at 09:17

Nitesh

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where am I going to add it ? this is my code – tp1 Jul 20 '13 at 09:30
It is mentioned above. Add it in App.xaml.cs – Nitesh Jul 20 '13 at 09:32

Ehsan · Answer 4 · 2013-07-20T10:30:12.810

0

why not use Mutex, You do this in App.xaml.cs.

 Mutex myMutex ;

 private void Application_Startup(object sender, StartupEventArgs e)
 {
    bool aIsNewInstance = false;
    myMutex = new Mutex(true, "MyWPFApplication", out aIsNewInstance);  
       if (!aIsNewInstance)
        {
          MessageBox.Show("Already an instance is running...");
          App.Current.Shutdown();  
        }
  }

edited Jul 20 '13 at 10:30

answered Jul 20 '13 at 09:45

Ehsan

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I didn't found Startup in event's visual studio window – tp1 Jul 20 '13 at 10:23
by the way I am using WPF – tp1 Jul 20 '13 at 10:25
where are you looking for it? Quick solution: Search in all files you will find it. – Ehsan Jul 20 '13 at 10:27
done, but didn't worked. – tp1 Jul 20 '13 at 10:58
@tp1 the code didn't work? or you didn't find it? – Ehsan Jul 20 '13 at 10:59
I have pasted the code bellow to my App.Xaml.cs File, – tp1 Jul 20 '13 at 11:01
that's all i have done !!! – tp1 Jul 20 '13 at 11:01
have you placed the debugger there to see is the code hit? have you changed this "MyWPFApplication" to your application name? – Ehsan Jul 20 '13 at 11:04
yes yes i have done that – tp1 Jul 20 '13 at 12:00
@tp1 is the debugger hit? – Ehsan Jul 20 '13 at 12:01

start single instance project

4 Answers4