November 10, 2010

History of Visual Basic


VB 1.0 was introduced in 1991. The drag and drop design for creating the user interface is derived from a prototype form generator developed by Alan Cooper and his company called Tripod. Microsoft contracted with Cooper and his associates to develop Tripod into a programmable form system for Windows 3.0, under the code name Ruby (no relation to the Ruby programming language).
Tripod did not include a programming language at all. Microsoft decided to combine Ruby with the Basic language to create Visual Basic.
The Ruby interface generator provided the "visual" part of Visual Basic and this was combined with the "EB" Embedded BASIC engine designed for Microsoft's abandoned "Omega" database system. Ruby also provided the ability to load dynamic link libraries containing additional controls (then called "gizmos"), which later became the VBX interface.

Timeline

  • Project 'Thunder' was initiated
  • Visual Basic 1.0 (May 1991) was released for Windows at the Comdex/Windows World trade show in Atlanta, Georgia.
  • Visual Basic 1.0 for DOS was released in September 1992. The language itself was not quite compatible with Visual Basic for Windows, as it was actually the next version of Microsoft's DOS-based BASIC compilers, QuickBASIC and BASIC Professional Development System. The interface used a Text user interface, using extended ASCII characters to simulate the appearance of a GUI.

Visual Basic for MS-DOS
  • Visual Basic 2.0 was released in November 1992. The programming environment was easier to use, and its speed was improved. Notably, forms became instantiable objects, thus laying the foundational concepts of class modules as were later offered in VB4.
  • Visual Basic 3.0 was released in the summer of 1993 and came in Standard and Professional versions. VB3 included version 1.1 of the Microsoft Jet Database Engine that could read and write Jet (or Access) 1.x databases.
  • Visual Basic 4.0 (August 1995) was the first version that could create 32-bit as well as 16-bit Windows programs. It also introduced the ability to write non-GUI classes in Visual Basic. Incompatibilities between different releases of VB4 caused installation and operation problems. While previous versions of Visual Basic had used VBX controls, Visual Basic now used OLE controls (with files names ending in .OCX) instead. These were later to be named ActiveX controls.
  • With version 5.0 (February 1997), Microsoft released Visual Basic exclusively for 32-bit versions of Windows. Programmers who preferred to write 16-bit programs were able to import programs written in Visual Basic 4.0 to Visual Basic 5.0, and Visual Basic 5.0 programs can easily be converted with Visual Basic 4.0. Visual Basic 5.0 also introduced the ability to create custom user controls, as well as the ability to compile to native Windows executable code, speeding up calculation-intensive code execution. A free, downloadable Control Creation Edition was also released for creation of ActiveX controls. It was also used as an introductory form of Visual Basic: a regular .exe project could be created and run in the IDE, but not compiled.
  • Visual Basic 6.0 (Mid 1998) improved in a number of areas including the ability to create web-based applications. VB6 has entered Microsoft's "non-supported phase" as of March 2008. Although the Visual Basic 6.0 development environment is no longer supported, the runtime is supported on Windows Vista, Windows Server 2008 and Windows 7.
  • Mainstream Support for Microsoft Visual Basic 6.0 ended on March 31, 2005. Extended support ended in March 2008. In response, the Visual Basic user community expressed its grave concern and lobbied users to sign a petition to keep the product alive. Microsoft has so far refused to change their position on the matter. (but see ) Ironically, around this time (2005), it was exposed that Microsoft's new anti-spyware offering, Microsoft AntiSpyware (part of the GIANT Company Software purchase), was coded in Visual Basic 6.0. Its replacement, Windows Defender, was rewritten as C++ code.

Derivative languages

Microsoft has developed derivatives of Visual Basic for use in scripting. Visual Basic itself is derived heavily from BASIC, and subsequently has been replaced with a .NET platform version.
Some of the derived languages are:
  • Visual Basic for Applications (VBA) is included in many Microsoft applications (Microsoft Office), and also in many third-party products like SolidWorks, AutoCAD, WordPerfect Office 2002, ArcGIS, Sage Accpac ERP, and Business Objects Desktop Intelligence. There are small inconsistencies in the way VBA is implemented in different applications, but it is largely the same language as VB6 and uses the same runtime library.
  • VBScript is the default language for Active Server Pages. It can be used in Windows scripting and client-side web page scripting. Although it resembles VB in syntax, it is a separate language and it is executed by vbscript.dll as opposed to the VB runtime. ASP and VBScript should not be confused with ASP.NET which uses the .NET Framework for compiled web pages.
  • Visual Basic .NET is Microsoft's designated successor to Visual Basic 6.0, and is part of Microsoft's .NET platform. Visual Basic.Net compiles and runs using the .NET Framework. It is not backwards compatible with VB6. An automated conversion tool exists, but fully automated conversion for most projects is impossible.
  • StarOffice Basic is a Visual Basic compatible interpreter included in StarOffice suite, developed by Sun Microsystems.
  • Gambas is a Visual Basic inspired free software programming language. It is not a clone of Visual Basic, but it does have the ability to convert Visual Basic programs to Gambas.

Performance and other issues

Earlier counterparts of Visual Basic (prior to version 5) compiled the code to P-Code only. The P-Code is interpreted by the language runtime, also known as a virtual machine. The benefits of P-Code include portability and smaller binary file sizes, but it usually slows down the execution, since having a runtime adds an additional layer of interpretation. However, small amounts of code and algorithms can be constructed to run faster than compiled native code.
Visual Basic applications require Microsoft Visual Basic runtime MSVBVMxx.DLL, where xx is the relevant version number, either 50 or 60. MSVBVM60.dll comes as standard with Windows in all editions after Windows 98 while MSVBVM50.dll comes with all editions after Windows 95. A Windows 95 machine would however require inclusion with the installer of whichever dll was needed by the program.
Visual Basic 5 and 6 can compile code to either native or P-Code.
Criticisms levelled at Visual Basic editions prior to VB.NET include:
  • Versioning problems associated with various runtime DLLs, known as DLL hell
  • Poor support for object-oriented programming
  • Inability to create multi-threaded applications, without resorting to Windows API calls
  • Inability to create Windows services
  • Variant types have a greater performance and storage overhead than strongly typed programming languages
  • Dependency on complex and fragile COM Registry entries
  • The development environment is no longer supported by Microsoft.

Legacy development and support

All versions of the Visual Basic development environment from 1.0 to 6.0 have been retired and are now unsupported by Microsoft. The associated runtime environments are unsupported too, with the exception of the Visual Basic 6 core runtime environment, which will be officially supported by Microsoft for the lifetime of Windows 7. Third party components that shipped with Visual Studio 6.0 are not included in this support statement. Some legacy Visual Basic components may still work on newer platforms, despite being unsupported by Microsoft and other vendors.
Development and maintenance development for Visual Basic 6 is possible on legacy Windows XP, Windows Vista and Windows 2003 using Visual Studio 6.0 platforms, but is unsupported. Documentation for Visual Basic 6.0, its application programming interface and tools is best covered in the last MSDN release before Visual Studio.NET 2002. Later releases of MSDN focused on .NET development and had significant parts of the Visual Basic 6.0 programming documentation removed. The Visual Basic IDE can be installed and used on Windows Vista, where it exhibits some minor incompatibilities which do not hinder normal software development and maintenance. As of August 2008, both Visual Studio 6.0 and the MSDN documentation mentioned above are available for download by MSDN subscribers.

Example code

Here is an example of the language: Code snippet that displays a message box "Hello, World!" as the window Form loads:
Private Sub Form_Load()
    ' Execute a simple message box that will say "Hello, World!"    MsgBox "Hello, World!"
End Sub
 
 
 
Source : http://en.wikipedia.org/wiki/Visual_Basic#History 

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