Visual FoxPro is a discontinued data-centric, object-oriented, procedural, programming language produced by Microsoft. It was derived from FoxPro (originally known as FoxBASE) which was developed by Fox Software beginning in 1984. Fox Technologies merged with Microsoft in 1992, after which the software acquired further features and the prefix "Visual". FoxPro 2.6 worked on Mac OS, DOS, Windows, and Unix. Visual FoxPro 3.0, the first "Visual" version, reduced platform support to only Mac and Windows, and later versions 5, 6, 7, 8 and 9 were Windows-only. The current version of Visual FoxPro is COM-based and Microsoft has stated that they do not intend to create a Microsoft .NET version.
Version 9.0, released in 2004 and updated in 2007, is the final version of the product.
Video Visual FoxPro
History
Visual FoxPro originated as a member of the class of languages commonly referred to as "xBase" languages, which have syntax based on the dBase programming language. Other members of the xBase language family include Clipper and Recital.
Visual FoxPro, commonly abbreviated as VFP, is tightly integrated with its own relational database engine, which extends FoxPro's xBase capabilities to support SQL query and data manipulation. Unlike most database management systems, Visual FoxPro is a full-featured, dynamic programming language that does not require the use of an additional general-purpose programming environment. It can be used to write not just traditional "fat client" applications, but also middleware and web applications.
In late 2002, it was demonstrated that Visual FoxPro can run on Linux under the Wine Windows compatibility suite. In 2003, this led to complaints by Microsoft: it was claimed that the deployment of runtime FoxPro code on non-Windows machines violates the End User License Agreement.
Visual FoxPro had a rapid rise and fall in popularity as measured by the TIOBE Programming Community Index. In December 2005, VFP broke into the top 20 for the first time. In June 2006 it peaked at position 12, making it (at the time) a "B" language. By September 2010, FoxPro and its variants had fallen out of the top 50, where it has remained ever since.
In March 2007, Microsoft announced that there will be no VFP 10, thus making VFP9 (released to manufacturing on December 17, 2004) the last commercial VFP release from Microsoft. The support of Version 9 ended on December 31, 2015.
At the time of the end of life announcement, work on the next release codenamed Sedna (named after a recently discovered dwarf planet) which was built on top of the VFP9 codebase had already begun. "Sedna" is a set of add-ons to VFP 9.0 of xBase components to support a number of interoperability scenarios with various Microsoft technologies including SQL Server 2005, .NET Framework, Windows Vista, Office 2007, Windows Search and Team Foundation Server (TFS). Microsoft released Sedna under the Shared source license on the CodePlex site. Microsoft has clarified that the VFP core will still remain closed source. Sedna was released on January 25, 2008. As of March 2008, all xBase components of the VFP 9 SP2 (including Sedna) were available for community-development on CodePlex.
In late March 2007 a grassroots campaign was started by the Spanish-speaking FoxPro community at MásFoxPro ("MoreFoxPro" in English) to sign a petition to Microsoft to continue updating Visual FoxPro or release it to the community as Open Source. On April 3, 2007 the movement was noted by the technical press.
On April 3, 2007, Microsoft responded to the petition with this statement from Alan Griver:
"We're very aware of the FoxPro community and that played a large part in what we announced on March 13th. It's never an easy decision to announce that we're not going to release another version of a product and it's one that we consider very carefully.
"We're not announcing the end of FoxPro: Obviously, FoxPro applications will continue to work. By some of our internal estimates, there are more applications running in FoxPro 2.6 than there are in VFP and FoxPro 2.6 hasn't been supported in many years. Visual FoxPro 9 will be supported by Microsoft through 2015.
"For Microsoft to continue to evolve the FoxPro base, we would need to look at creating a 64-bit development environment and that would involve an almost complete rewrite of the core product. We've also invested in creating a scalable database with SQL Server, including the freely available SQL Server Express Edition. As far as forming a partnership with a third-party is concerned, we've heard from a number of large FoxPro customers that this would make it impossible for them to continue to use FoxPro since it would no longer be from an approved vendor. We felt that putting the environment into open source on CodePlex, which balances the needs of both the community and the large customers, was the best path forward."
Version Timeline
All versions listed are for Windows.
Maps Visual FoxPro
Code samples
The FoxPro language contains commands quite similar to other programming languages such as Basic. Loops include do, if, while, for, else commands in a usage easily understood by anyone familiar with other programming languages. Commands take the form of "command" and "endcommand"
Some basic syntax samples:
Hello World example:
Object
- VFP has an extensive library of predefined classes and visual objects which are accessed in the IDE by a Property Sheet (including Methods), so code such as the above defining classes and objects are only needed for special purposes and the framework of large systems.
Data handling
The language also has extensive database manipulation and indexing commands. The "help" index of commands in VFP 9 has several hundred commands and functions described. The examples below show how to code the creation and indexing of tables, however VFP has table and database builder screens which create the tables and indexes without making you write code.
ODBC access using SQL passthrough
References
External links
Microsoft pages
- Main Visual FoxPro Microsoft page
- MSDN FoxPro support board
- VFP's online help
- Visual FoxPro Downloads page
Other pages
- Visual FoxPro Wiki A repository of FoxPro information (written in VFP)
- A site devoted to the history of FoxPro
- VFPx A Visual FoxPro Community effort to create open source add-ons for VFP 9.0
- PortalFox A Hispanoamerican Community Portal for VFP developers
Source of article : Wikipedia
0 Comments