Nested Classes, Variable Scope, and method scope.

If I do that I lose my organization. I end up with a class called Version4. Version 4 of what?

The way I had it before it was: ApplicationName.Version4.Function

You are proposing Version4.Function ?

If I use a Namespace with your solution can I get ApplicatioinName.Version4.Function ?

Also, with your suggestion, will the variable server be the same for every instance of the class Version 4?

The server variable will be the same for all instances of all classes that inherit from Main.

Namespaces might be one way to solve your problem. You may also consider isolating these classes into their own project, in which case the names become <ProjectName>.Version4, <ProjectName>.Version5, etc

Can I add a project type of "Class" or ???

You can create a project of type "class library". You won't be able to run this directly, since there's no UI... but you can reference it from other projects.

Ok, I think we are on the right track. I added a class library project, but I can't figure out how to reference it.

I tried an import statement and I tried projectname.class and solution.project.class. Nothing is working.

You need to right-click on the project in the solution explorer, then "add reference." Other projects in the solution will be visible in the "Projects" tab.

That worked well. We are making progress. Still have a few questions.

When I declare an instance of projectname.version4 can I hide some of the functions that are inherited from the MustInherit class Main? I don't want to accidentally call project.version4.parentOnly when it should be called as project.parentOnly.

Also, can my Class Library project reference classes in my other project or should I create a class library for each main class?

Your class library can reference anything except projects that reference it either directly or indirectly.

As far as hiding methods... I guess I'm not sure what you're after here. One of the nice thing about the MustOverride methods is that there's no method in the base class that can be called -- it always goes through to the child implementation (that is, the if statement to determine which flavor of "GetFiles" to call is gone).

I think you'll see that Project.ParentOnly is a class, not a method -- so I'm not sure there's room for confusion there. If you're trying to differentiate between Project.Main.Foo and Project.Version4.Foo... well, there are a couple different ways we can do that, depending on you reasoning for having the same method in both the parent and child classes.

Let's ignore the ParentOnly issue (not real important to me) for a minute and talk about the references.

">" means "makes reference to"

Project > class library
project > shared functions
class library > shared function

Will the about references cause problems?

Nope.

What would cause problems is this: Main Project >> Class Library Project >> Shared Function Project >> Main Project

Since I am new to classes I am trying to figure out how to share things throughout my whole application. I use to just use Modules and that worked fine for project scope. If I use class libraries then I need functions that are solution scope.

My shared functions contain things like: logging, debug functions, event log, etc...... If you were writing an app how would you make these function globally available to all your classes in all your projects?

Also, how would you get a variable (like a log path) into your shared functions in a way that you didn't have to pass the variable everytime you called the shared function?

I'd start by looking at Enterprise Library for logging. :)

Typically, something like logging gets put into it's own project that is accessible from everywhere in the solution (that is, it's nicely isolated). You'd end up having a shared methods (functions) in the logging class, with a shared property as well to store the path.

Alternately, you could look at the singleton pattern... but that's not required.

Using the code below, you could call MyLogger.Log(message) from anywhere in your solution that had a reference to your logging project. One nice feature of this approach is that you can include your logging project in any solution, and you'll have access to the logging features.

Public Class MyLogger
	Private Shared _loggingPath As String
	Public Shared Property LogginPath() As String
		Get
			Return _loggingPath
		End Get
		Set(ByVal value As String)
			_loggingPath = value
		End Set
	End Property
 
	Public Shared Sub Log(ByVal message As String)
		' do your logging here
	End Sub
End Class

                                              

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You are my hero. I hate rewriting code.

What about having two classes inherit from each other?

class events
inherits logging
end class

class logging
inherits events
end class

That won't work. What you'll need to do is take the common code and create a base class that both inherit from.

In your very first post I changed your code from:

Public MustInherit Class Main

to

Public Class Main

That way I can have an instance of Main by itself. Now the variable server is a separate value for each instance of version4 which I don't want. Suggestions?