VB Classes And Objects Miscellany by George Hernandez

VB uses the following mechanisms to implement objects and classes:
- Type libraries store a group of classes together.
- Object browsers are used to view type libraries.
- References in a project are type libraries that your project has accessed.
A container is any object that can have other objects in it. EG:
- An OLE container (like a Microsoft Word document) may have OLE components (like a Microsoft Excel document).
- An ActiveX container (like a browser) may have ActiveX controls (like a date picker).
A class can be data aware.
- A class is said to be a data consumer if the class can bind directly to an external source of data.
- A class is a data source/provider if the class can take data from an external source and provide it to other objects.
If you make your object variable as Object and then later set the object variable to a specific object type, you can determine the object type by using the TypeName function. EG:
```
lngDataTypeOfObject = TypeName(objAnyObject)
```
OOP (Object Oriented Programming) is concerned with building object-based component software (eg use C++ to make a component). ActiveX is concerned with combining object-based component software (eg use VB).
If the object you are using is one of several, you may programmatically make calls to different methods or properties by utilizing the CallByName function. EG:
```
CallByName Text1, "MousePointer", vbLet, vbCrosshair
Result = CallByName (Text1, "MousePointer", vbGet)
CallByName Text1, "Move", vbMethod, 100, 100
```
You can perform multiple actions upon a single object by using the With...End With statement. EG:
```
With obj
   .Height = 32
   .Run
End With
```
Me is a VB keyword that is available in all class modules. It is an object variable equivalent to the current instance of the class.

Page Modified: (Hand noted: 2007-09-24 20:00:30Z) (Auto noted: 2007-11-17 06:36:54Z)