The language in which algorithms in the PROMOTIC system are written, is Visual Basic
(more precisely said, its scripting part), often marked as VBScript
. It goes probably about the simplest computer language that can be easily learned.
VBScript vs. Visual Basic and VBA:
Visual Basic is created so as it would help developers quickly and easily to create otherwise complicated OS Windows
applications. The language represented for programming the same as the text editor WYSIWYG
did for creating documents.
Visual Basic for Application (VBA)
is the subset of the Visual Basic
language. It means that it is similar to it but it hasn't got all its capability. VBA
is integrated with applications like Microsoft Excel
. In the Microsoft Office
package there is integrated VBA
into the Microsoft Word
application and all other members of the Office
is the subset of VBA
. It goes about the very simple yet full programming language. It doesn't offer all comforts of the Visual Basic
uses the method "sand castle" with respect to the security. Its meaning lies in that VBScript
reserves a part of resources and memory of the computer for itself. It can do anything, it wants in the sand castle but it can never leave it and damage the data in the rest of the computer memory. It means that pure VBScript
cannot access the computer memory neither create or work with files on the disk. In practice, all statements that were "dangerous" in some manner (it means that they could be used for creating a virus), were removed.
Thus we get a very safe environment on one side, but we lose a lot of important and required possibilities at the same time. Like always, the solution exists. In VBScript
it is possible to use objects. Each object can have lots of methods, and these methods can be created so that they can do nearly everything. Each Pma object
, etc.) is understood as the object in VBScript
, and all its properties and methods can be called. At the same time the special and unique Pm
object can be used in VBScript
that contains all required methods which don't belong to any concrete Pma
object. In this object there are, for example, methods for the access to disk. By this, the VBScript
language is extended beyond its limits.
For the initial familiarization with the VBScript language and its using in the PROMOTIC system we recommend to go through in chapter PROMOTIC Coursebook
, section Out First Script