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Resource Logic Client/Server Development Services
Legacy Maintenance
Visual Basic 6
Visual Basic 6 was the point in language development where the 32-bit programming
environment became useful to the run-of-the-mill business programmer. One can
trace a path from the 1960s: Cobol on mainframes, various proprietary languages, many
based on either C++ or Basic on minicomputers, GW and QuickBasic on microcomputers, and
dBase and Foxpro on the larger networked PCs of the late 1980s and early 1990s.
The 80386 CPU was introduced in 1986, although early boxes could easly cost $10,000.
With the emergence of Windows 98 and NT 4.0, programmers could quit thinking about extended
memory managers, 16-bit integer data types, and slicing programs into .DLLs and overlays.
Visual Basic 1 arrived in 1991, operating primarily on 16-bit computers.
The trial and error process of understanding how the language would be used, the operational
consequences of design decisions, integration of true 32-bit operating systems, and the
'cousin' (Visual Basic for Applications, seen primarily in Microsoft Access) evolved into
the critical mass necessary for the language to dominate the desktop custom programming
environment in the late 1990s. Someone that wanted to create a distributable, database
driven order entry system could do so without having to think much about the memory
environment, operating system, or database interface. The consequence was an explosion
of VB6 apps. There are national banking systems in various parts of the world still
running business critical applications based on VB6. It is common to find 'help-wanted'
ads seeking to hire dozens of VB6 programmers.
There were a number of critical issues with VB6 that Microsoft addressed in the
emergence of the CLR (.NET) languages. One was a huge divide between Web-based and
Windows-based programming, another was security issues, and a third was support for
extensive interface libraries. In comparison to VB6, the VB.NET (and C#) development
platforms do an enormous amount of work for the programmer. In many cases, however,
this is overkill. In a situation where a business needs to control their desktop,
VB6 can get a form on the screen, communication with an SQL database, and printer support
with a minimum of bother.
VB6, and it's lookalikes, has wormed it's way into dozens of computing platforms,
including mobile (Pocket PC), Linux derivatives, embedded control, Java Runtime Environment
(JRE), and so on. It is commonly used as a 'middleware' layer in web applications,
typically for making calls to SQL databases, and formatting the returned rowsets in HTML
or XML. The 'sweet spot' ran from 1998, when VB6 was released, to 2003, when the
.NET technologies began to usurp the distinct Winforms and Web deployment platforms.
This was concurrent with the .COM boom, and literally millions of applications and
components were developed.
As a result, there are tens of thousands of legacy applications operating, many of
which are nearly invisible. 'Nearly invisible' might be COM components integrated with
Microsoft Access (or other Microsoft Office products), .DLLs invoked by web scripts, SQL
Server packages, PDA or embedded control, or Winforms applications that are in effect,
embedded control. One example that came to light was when a managed services company
was asked up upgrade the access control system for a 35 story building: when the computer
was finally located it was discovered it was running Windows 95 - unmodified - since the
system had been put in in the mid 1990s.
Users that have legacy web or desktop applications may be using COM-based VB products
unknowingly, and are (or will be) exposed to a rude shock in a situation where they need
to migrate to a new box or platform.
If you have any questions, you may eMail us at
Info@ResourceLogic.Net
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