How to make a hierarchical structure Class

[maximas2000]

hi friends ...

i'm intending to make an application with visual basic 6.0

the application will solve some design proplems of civil enineering like design a beam , columns

and also to make a workshop drawing through the program by programming AutoCAD

to make this i'll make a ActiveX.dll component

to collect some useful functions of math, registery and so on

i want to make a parent class named sceeda

inside the activeX.dll component

and other classes like Math , Design, and so on

my question is :
****************

ho to make a hierarchical structure fashion so i can call the math class from the main class Sceeda

in other words ...


what code i write inside the ActiveX.dll allowing me to call a function in the Math Class from sceeda Class like this :

Sceeda.Math.CalculateAverage

where :

Sceeda :
********
the main class in the ActiveX.dll and have no functions ( the class is nearely empty)

Math:
******
the class i wrote the function or procedure called CalculateAverage

how to make a relation between 2 classes

i don;t want to call the math class directly from my application like this :

Math.CalculateAverage


N.B :

i'dont want to make inheritence

but something like aggregation

any one help me please

so many thanks

urs maximas

[Phil Weber]

Create an ActiveX DLL project (SceedaUtility). Add a new Class module (CSceeda). Add the following code to the class:

Option Explicit
Public Math As CMath

Private Sub Class_Initialize()
    Set Math = New CMath
End Sub

In the Properties Window, set the CSceeda class' Instancing property to MultiUse or GlobalMultiUse.

Now add a second Class module to the project (CMath). Add the following code to the class:

Option Explicit
Public Function CalculateAverage(Values() As Double) As Double

    Dim Result As Double

    ' Calculate average here

    CalculateAverage = Result

End Function

Set this class' Instancing property to PublicNotCreatable. Compile the project to build the DLL.

Finally, open or create the client project. Set a reference to your new SceedaUtility DLL. In your client code, do this:

Dim Sceeda As CSceeda
Set Sceeda = New CSceeda

Dim Values(4) As Double
Dim Average As Double
Average = Sceeda.Math.CalculateAverage(Values)

[maximas2000]

working 100 % successfull

thank u sir Phil

urs maximas