Previous Instance of an application

[MTSkull]

I need to expand on the info in this thread with a bit of twist.

 

If a previous instance of the application is found I want to ask the user if they want to kill it (the previous instance and not the current.) I will end the current if they choose no, but how do I Kill the previous. Don't need complete code just pseudo code will be fine, and hint of where to start.

 

 

   Public Function PrevInstance() As Boolean

       Dim ReturnValue as Boolean = False

       If UBound(Diagnostics.Process.GetProcessesByName( _
        Diagnostics.Process.GetCurrentProcess.ProcessName)) > 0 Then
           Dim Message As String

           Message = "A previous instance of this program is currently running."
           Message += "  Do you want to end the other program?"

           If MsgBox(Message, MsgBoxStyle.YesNo, "Kill Prev App") _
            = MsgBoxResult.Yes Then

               'Kill Prev app or apps here

           Else
               ReturnValue = True
           End If

       End If

       Return ReturnValue

   End Function

 

MTS

[PlausiblyDamp]

Something like

Public Function PrevInstance() As Boolean

Dim ReturnValue As Boolean
Dim apps() As System.Diagnostics.Process
apps = Diagnostics.Process.GetProcessesByName(Diagnostics.Process.GetCurrentProcess.ProcessName)

If apps.Length > 1 Then
Dim Message As String
Message = "A previous instance of this program is currently running."
Message &= "  Do you want to end the other program?"

If MessageBox.Show(Message, "Kill Prev App", MessageBoxButtons.YesNo) = DialogResult.Yes Then

For Each p As Process In apps
             If p.Id <> Process.GetCurrentProcess.Id Then
	    p.Kill()
             end if
Next
       Else
Return True
       End If
End If

Return False

End Function

should do the trick - although be aware the .Kill method will terminate the application without giving the user the chance to save any work etc.

Edited June 10, 2004 by PlausiblyDamp

[PlausiblyDamp]

Here's a safer version as it requests the other applications to close - this way any cleanup code (form_close etc) code will be executed.

Public Function PrevInstance() As Boolean

	Dim ReturnValue As Boolean

	Dim apps() As System.Diagnostics.Process
	apps = Diagnostics.Process.GetProcessesByName(Diagnostics.Process.GetCurrentProcess.ProcessName)

	If apps.Length > 1 Then

		Dim Message As String

		Message = "A previous instance of this program is currently running."
		Message &= "  Do you want to end the other program?"

		If MessageBox.Show(Message, "Kill Prev App", MessageBoxButtons.YesNo) = DialogResult.Yes Then

			For Each p As Process In apps
				If p.Id <> Process.GetCurrentProcess.Id Then
					SendMessage(p.MainWindowHandle(), WM_CLOSE, UIntPtr.Zero, IntPtr.Zero)
				End If
			Next
		Else
			Return True
		End If

	End If

	Return False

End Function

[MTSkull]

Made a few tweaks. Since I am not worried about saving data in the other programs I am just going to kill them outright. Otherwise I would opt for the safer route.

   Public Function PrevInstance() As Boolean
       Dim ReturnValue As Boolean = False

       Dim apps() As System.Diagnostics.Process
       Dim CurrentProcess As System.Diagnostics.Process

       CurrentProcess = Diagnostics.Process.GetCurrentProcess
       apps = Diagnostics.Process.GetProcessesByName(Diagnostics.Process.GetCurrentProcess.ProcessName)


       If apps.Length > 1 Then

           Dim Message As String

           Message = "A previous instance of this program is currently running."
           Message &= "  Do you want to end the other program?"

           If MessageBox.Show(Message, "Kill Prev App", MessageBoxButtons.YesNo) = DialogResult.Yes Then

               For Each p As Process In apps
                   If p.Id <> CurrentProcess.Id Then p.Kill()
               Next
           Else
               ReturnValue = True
           End If

       End If

       Return ReturnValue

   End Function

 

Thanks for the help

MTS

[MTSkull]

Just looked up the "Return" keyword in F1. I understand now, learn something new every day.

 

Thanks Again

MTS