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Posted on 2003-12-10
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Last Modified: 2013-11-25
I'm wanting to write an object that behaves like MS Outlook in that when I go to get a refrence to it, if it's already running it will return the running instance. Is this possible in VB? Would or Could I do this as an ActiveX Exe project?

Dim MyObject as MyObject
Set MyObject = new MyObject
'if the object is already running, I want the currently running instance. So, theoretically I might have several refrences to it.
Any Ideas?
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Question by:Bilbo_Baggins2
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11 Comments
 
LVL 27

Expert Comment

by:Dabas
ID: 9915303
Hi Bilbo_Baggins2:
> Would or Could I do this as an ActiveX Exe project?
Yes

Dabas
0
 

Author Comment

by:Bilbo_Baggins2
ID: 9915655
I wrote a test program... I have one property that's a string. I want to set the property in the first instance then see that string when I read the property in each new Standard EXE instance I start. The test below doesn't work right. It's starting a new instance of clsTest each time I spawn it in the standard EXE. How do I get it to return the instance of the already running class?

The ActiveX Exe project is named clsTest and has the following code:
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Private sName As String

Public Property Get NameOfInstance() As Variant
    NameOfInstance = sName
End Property

Public Property Let NameOfInstance(ByVal vNewValue As Variant)
    sName = vNewValue
End Property
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''

The Standard Exe project has the following code:
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Dim oTest As clsTest.clsTesting

Private Sub Command1_Click()
    oTest.NameOfInstance = "Jeff"
End Sub

Private Sub Command2_Click()
    Label1 = oTest.NameOfInstance
End Sub
'also tried createobject
Private Sub Form_Load()
    Set oTest = New clsTest.clsTesting
End Sub
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
0
 
LVL 27

Expert Comment

by:Dabas
ID: 9916039
Bilbo_Baggins2:
Is the ActiveX Exe program running in the background?

Dabas
0
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Author Comment

by:Bilbo_Baggins2
ID: 9916277
>Is the ActiveX Exe program running in the background?

Yes, it's running in the background. When the first Standard exe starts it starts the ActiveX Exe if it isn't running yet.

Although the code above will start the ActiveX Exe.
0
 
LVL 27

Expert Comment

by:Dabas
ID: 9916352
Bilbo_Baggins2:
What does the instancing property for the project show?

Dabas
0
 

Author Comment

by:Bilbo_Baggins2
ID: 9916380
5 - MultiUse
0
 
LVL 27

Expert Comment

by:Dabas
ID: 9916449
Bilbo_Baggins2:
Try to change to GlobalSingleUse

IF that fails, then try one of the other settings

Dabas
0
 

Author Comment

by:Bilbo_Baggins2
ID: 9916544
that doesn't seem to work either. It still seems to be creating each new one as a new instance.
0
 
LVL 28

Accepted Solution

by:
AzraSound earned 1600 total points
ID: 9916673
You need to add your ActiveX EXE into the ROT (Running Object Table).  This sample shows you how to do that:
http://www.planet-source-code.com/vb/scripts/ShowCode.asp?txtCodeId=12319&lngWId=1
0
 
LVL 27

Expert Comment

by:Dabas
ID: 9917102
Bilbo_Baggins2:
I leave you in Azra's very capable hands!

Dabas
0
 

Author Comment

by:Bilbo_Baggins2
ID: 9917555
Thanks Azra. That's exactly what I needed.

And thanks to you, Dabas. I appreciate the effort!
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