Now a solid tool, Visual Basic's poised to become a cult classic

Visual Basic, one of the most popular development tools ever to
hit shrink-wrap, has eased a generation of custom application programmers into the Windows
environment. At the same time, it spawned a whole industry of add-on tools.


Detractors call Visual Basic a toy language without the depth or cross platform
portability for enterprise work. Although it's come a long way from its first release, the
product hasn't been upgraded since Version 3.0 way back in 1993.


Now, Microsoft wants us to accept Visual Basic 4.0 Enterprise Edition for Windows 3.x,
Windows 95 and Windows as a serious enterprise client server development tool. Will users
take it as seriously as Microsoft does?


Based on what I've seen, 4.0 undoubtedly will become a cult classic of visual
programming. It goes far beyond the current generation of front-end tools, but it's no
cure-all for every application development pain.


The distribution CD-ROM includes Visual SourceSafe 4.0, a version control and team
development system that manages programming projects in Visual Basic and Microsoft's
Visual C++. The CD also includes a Microsoft Developer Network starter kit with technical
articles and sample code.


But that's only on the surface. This front-end program has been tooled up as a 32-bit
distributed computing platform ready to give advanced client server applications access by
Object Linking and Embedding to data on Windows NT and Windows 95 application servers.


The Remote Automation Connection Manager registers OLE objects as remote automation
objects and manages access to them. You can put these objects into client apps like any
other Visual Basic custom control, and data gets passed by remote procedure calls across
the network for processing.


Visual Basic 4.0 uses 32-bit OLE custom controls, or OCXes, as its primary control
type. Fortunately, you still can use the old 16-bit .VBX control types, so you won't have
to run out and immediately upgrade all your VBX packages.


But you won't be able to use all of Microsoft's OCXes. Those included with Visual
FoxPro 3.0 [GCN, Sept. 18, Page 31] are incompatible; FoxPro was shipped
before the Visual Basic OCX standard became final.


Visual Basic 4.0 has the latest 32-bit version of Microsoft Access's Jet database
engine. It supports replication between distributed databases, copying updates from one to
another.


To run Visual Basic 4.0 at its full 32-bit potential under Windows NT, there's a price:
You must upgrade your servers to NT 3.51. Earlier versions including NT 3.5 can run only
the 16-bit version of Visual Basic 4.0 and can't deal with Visual SourceSafe or remote
automation objects.


The same goes for Windows 3.1 platforms. They can access the remote automation objects
but can't make use of version control or act as servers.


I found 4.0 rather clumsy at simple database functions such as inserting a row in an
active database table. The Structured Query Language and xBase have relatively direct
command sets to do things like this, but there's no easy way to add a record without
relying exclusively on the data controls.


Browsing for advice in the help files was akin to looking up a definition in a
thesaurus. Although the on-line documentation is fairly complete, its organization and key
words don't give much help to database programmers who know xBase or other languages.


That's more a function of the language structure than of the documentation. Visual
Basic is a jack-of-all-trades language. It relies heavily on manipulating custom controls
and their properties to provide data access and other specialized functions, much the way
C++ relies on class libraries. This makes building application interfaces straightforward,
but it also makes working around some control limitations frustrating.


Because of Visual Basic's modular nature, some developers will regard it as a perfect
mate to Visual C++ and other development environments. It has a ready-made, distributed
OLE environment, so you can wrap industrial-strength software components as remote
automation objects on a Windows NT server.


There are plenty of other features, including drivers for Microsoft SQL Server and full
compatibility with code from Microsoft's Visual Basic for Applications and the Microsoft
Office suite.


Visual Basic 4.0 Enterprise Edition lists at $995. Users of the Visual Basic 3.0
Professional Edition can upgrade for about $500. Discounts for General Services
Administration contracts are expected before the end of the year.


If you're looking for a way to test the waters of distributed client-server, the 4.0
Enterprise Edition is a good start. But if your network isn't all Microsoft, there'll be
holes to fill.


About the Author

Sean Gallagher is senior contributing editor for Defense Systems.

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