Restricting only one copy to run

[pachjo]

Hi,

My app now has the ability to open a .chm help file to help the user learn how to use my app.

I use process.start to achieve this but notice a new window opens with every click which is rather naff!

I have tried to track the process and identify if one is running with little success.

I know nothing about threading....the topic makes me hide under my rock

Do I have to enter this realm to achieve the results I want?

Thanks for any help forthcoming

 

[JuggaloBrotha]

so you want only 1 copy of your program to run at a time? or only one copy of the help file to be open at a time?

For the help file, use:

Help.ShowHelp(Me, "HelpFile.chm")

for the one instance of the program:

    Private Sub frmMain_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        If PrevInstance() = True Then Me.Close()
    End Sub


    Private Function PrevInstance() As Boolean
        If UBound(Diagnostics.Process.GetProcessesByName(Diagnostics.Process.GetCurrentProcess.ProcessName)) > 0 Then
            Return True
        Else
            Return False
        End If
    End Function

 

[pachjo]

Kool, the help restriction works a treat thanks

Handy too to see how to restrict one copy of the application to run also, thanks again

 

[pachjo]

Mmm cannot get the app version to run, does not like ti Ubound command which is old vb which I don't use and can't get the .net way to work?

any tips?

 

[JuggaloBrotha]

i guess UBound is used there, i'll make a .net one:

    Private Function PrevInstance() As Boolean
        If CInt(Diagnostics.Process.GetProcessesByName(Diagnostics.Process.GetCurrentProcess.ProcessName).GetUpperBound(0)) > 0 Then
            Return True
        Else
            Return False
        End If
    End Function

 

[CliffB82]

I'm using VB2005 and compact framework. It appears that the GetProcessesByName function is not supported. Do you know haw to prevent multiple instances of a program running on the compact framework?

 

[JohnH]

Thread was moved to CF forum section.