6 replies to this topic

[PogBender]

i made vb coded DLL .
i made Two Programs
The first changes variable value in the DLL
The Second Read This variable
So:
Two programs that use one DLL.

it dont works

ty :P

[CommittedC0der]

Umm do you have some code we can look at, to try and find the error? Or the problem your getting?
~ Committed.

[PogBender]

here is the simplest Code:

Imports System.IO

Public Class GetSetData

    Dim Num As Integer = 6

    Function GetD()

        Dim Ans As Integer

        Ans = Num

        Return Ans

    End Function

    Public Sub SetD(ByVal Num1 As Integer)

        Num = Num1

    End Sub

End Class

abd ther is one App that use the SetD
and other use the GetD

after i use the SetD and change the value of Num
when i call the GetD Function the number is still 6

ty :P

[PogBender]

BUMP

[Alexander]

PogBender said:

BUMP

From an outside perspective (it has been somewhat a decade since I had touched visual basic) it looks like you will need to use the property statement, and not the sub for a function:

Class Class1    ' Define a local variable to store the property value.
    Private propertyValue As String
    ' Define the property.
    Public Property prop1() As String
        Get
            ' The Get property procedure is called when the value
            ' of a property is retrieved.
            Return propertyValue
        End Get
        Set(ByVal value As String)
            ' The Set property procedure is called when the value 
            ' of a property is modified.  The value to be assigned
            ' is passed in the argument to Set.
            propertyValue = value
        End Set
    End Property
End Class

This can allow prop1() to return "propertyValue" and prop1("something") to set "propertyValue" (from what I gather)

Resource from: http://msdn.microsof...y/zzh9ha57.aspx

----

As a side note, you should decide on the scope of the variable created. "dim" may be public, when you wish for "private" (only available to the class)

[LuthfiHakim]

Without special treatment, no matter what programming language is, you will always get this problem. And this is actually by design. Any memory allocated by a dll will be done in the memory space allocated to the application that load the dll. So your dll variable for application #1 will be different with dll variable for application #1. Yes, each application get their own copy of dll variable.

One of the solution for your problem is by using memory mapped files. With this, each application can share the same variable. See example of how the memory mapping is done in this tutorial (see under Dynamic-Link Library). It was in Delphi, but I hope you can see how it's done, and to implement it in vb.

[PogBender]

TY very much,both of you.
i'll try it.
:P