Overview of AutoCAD Visual Basic for Applications (VBA) Interface
Microsoft
VBA is an object-oriented programming environment designed to
provide rich development capabilities similar to those of Visual
Basic 6 (VB). The main difference between VBA and VB is that VBA
runs in the same process space as AutoCAD, providing an
AutoCAD-intelligent and very fast programming environment.
VBA also
provides application integration with other VBA-enabled
applications. This means that AutoCAD, using other application
object libraries, can be an Automation controller for other
applications such as Microsoft Word or Excel.
The
standalone development editions of Visual Basic 6, which must be
purchased separately, complement AutoCAD VBA with additional
components, such as an external database engine and report-writing
capabilities.
There are
four advantages to implementing VBA for AutoCAD:
VBA and its environment are easy to learn and use.
VBA runs in-process with AutoCAD. This translates to very fast
program execution.
Dialog box construction is quick and effective. This allows
developers to prototype applications and quickly receive feedback
on designs.
Projects can be standalone or embedded in drawings. This choice
allows developers great flexibility in the distribution of their
applications.
NoteMicrosoft has
not promised to provide 64-bit VBA SDK libraries (.dll).
Subsequently, 64-bit AutoCAD can no longer run VBA as an in-proc
component; VBA components now run as 32-bit out-of-process COM
components, and provides a stopgap arrangement for 64-bit AutoCAD
VBA users. This arrangement might require a few changes to existing
VBA code. This stopgap provision would be deprecated in future
versions of AutoCAD and it is advisable for the users to port their
exisiting VBA code to VB. NET.
