Custom Classes and Custom objects. General and UserForms
We are approximately ¾ into the story and have reached the part which touches on the area often at the start of traditional explanations of these things. The previous discussions told us that we, when using Excel, are somewhere down from the true Class level, having access to objects already built from a Class which we had no direct access to.
Excel VBA does allow us to start at the top, all be it with a limited possibilities in what we can achieve and do. We have two possibilities.
The first starts with being able to add a code module which is at the level of a Class. This is misleadingly seen in the VB Editor as similar to the other modules, whereas its pseudo up a level , and is intended to be a Blue print / Template from which objects are then instantiated.
To confuse us further , those instantiated objects , would have a similar place in the OOP hierarchy as those two object types discussed which we can see. But the object code modules we can effectively make from our custom class module, are not represented in the VB Editor.
Having already made a confusing mess, as is typical with Microsoft, they like to take it further, and these unrepresented objects can be many, since we are free to instantiate as many objects from the Class as we choose.
The second, a UserForm is a slightly different thing altogether, and we will only discuss some basics of this in particular things relevant to our general Class discussions, for completeness. ( For anyone familiar with the “ stand alone “ Form/Window applications of traditional Visual Basic, the UserForm is very approximately a similar idea for a semi independent Window type application , but within Excel , rather than anywhere within Windows, as with the traditional “ stand alone “ Form/Window of Visual Basic )
Before discussing , further , some general notes specifically concerning the usefulness of using Class / Class modules, in particular the use of Class modules, ( not necessarily directly related to UserForms )…
Some general discussions about the ( non ) usefulness of using Class / Class modules
_ There is not much, if anything that can be done with Class Modules that can’t be done with normal VBA Functions. There is little if any, performance advantages. There is no increase in functionality or efficiency
_ For somebody writing a lot of complicated coding it can help that person to both organise and later remember what you were doing. Related coding can be kept in the same place, and it helps make the coding self documenting. At the same time it makes the coding more difficult for someone else to follow and understand. So it is a useful tool to help you organise complicated long coding, and if you want to share and make it a bit more difficult for someone else to understand.
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