Visual FoxPro

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Microsoft Visual FoxPro
Typical VFP9 editing session
Design by	Microsoft Corporation
Latest release	Visual FoxPro 9.0 Service Pack 2 (SP2) / October 11, 2007
OS	Microsoft Windows
Platform	x86 and greater
Available in	IDE: English, German, Spanish Runtime: Above, French, Chinese, Russian, Czech, Korean
Development status	Maintenance mode
Genre	Database Programming language
License	Microsoft EULA
Website	msdn.microsoft.com/vfoxpro

Visual FoxPro is a data-centric object-oriented and procedural programming language produced by Microsoft. It is 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". The last version of FoxPro (2.6) worked under Mac OS, DOS, Windows, and Unix: Visual FoxPro 3.0, the first "Visual" version, dropped the platform support to only Mac and Windows, and later versions 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.

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. (A history of the early years of xBase can be found in the dBASE entry.)

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.

[edit] Recent history

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.^[1]

In December 2005, VFP broke into the top 20 on TIOBE's Programming Community Index for the first time. In March 2007 it was at position 19, making it a "B" language, and as of August 7, 2007 it dropped into position 22.

In March 2007, Microsoft announced "that there will be no VFP 10"^[2], thus making VFP9 (released to manufacturing on December 17, 2004) the last commercial VFP release from Microsoft. The support of Version 9 is ongoing with service packs that were released December 8, 2005 and October 11, 2007.

At the time of the end of life announcement, work on the next release codenamed Sedna 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 ^[3]. As of March 2008, all XBase components of the VFP 9 SP2 (including Sedna) were available for community-development on the CodePlex.

Meanwhile, some of the FoxPro-related technology can be seen in other Microsoft products such as SQL Server, Team Foundation Server and various portions of the .Net Framework.

In late March 2007 a grassroots campaign was started by the Spanish-speaking FoxPro community at MasFoxPro (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.^[4]

Also on April 3, 2007 Microsoft responded to the petitioner's requests 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."

[edit] Version information

[edit] Operating system compatibility

[edit] Information on executable files

[edit] Code samples

Hello World example:

MESSAGEBOX("Hello World")

[edit] Object

Output of the Hello World program.

loForm = CREATEOBJECT("HiForm")
loForm.Show(1)
 
DEFINE CLASS HiForm AS Form
  AutoCenter = .T.
  Caption = "Hello, World"
 
  ADD OBJECT lblHi as Label WITH ;
    Caption = "Hello, World!"
ENDDEFINE

loMine = CREATEOBJECT("MyClass")
? loMine.cProp1   && This will work. (Double-ampersand marks an end-of-line comment)
? loMine.cProp2   && Program Error: Property CPROP2 is not found.
 
? loMine.MyMethod1()  && This will work.
? loMine.MyMethod2()  && Program Error: Property MYMETHOD2 is not found.
 
DEFINE CLASS MyClass AS Custom
  cProp1 = "My Property"    && This is a public property
  HIDDEN cProp2     && This is a private (hidden) property
 
  PROCEDURE Init()    && Class constructor
    This.cProp2 = "This is a hidden property."
  ENDPROC
 
  PROCEDURE MyMethod1()
    * This is a public method, calling a hidden method that returns
    * the value of a hidden property.
    RETURN This.MyMethod2()
  ENDPROC
 
  HIDDEN PROCEDURE MyMethod2()  && This is a private (hidden) method
    RETURN This.cProp2
  ENDPROC
ENDDEFINE

[edit] Data handling

&& Create a table
CREATE TABLE randData (iData I)
 
&& Populate with random data using xBase and SQL DML commands
FOR i = 1 TO 50
    APPEND BLANK
    REPLACE iData WITH (RAND() * 100)
 
    INSERT INTO randData (iData) VALUES (RAND() * 100)
ENDFOR
 
&& Place a structural index on the data
INDEX ON iData TAG iData
CLOSE ALL
 
&& Display sorted data using xBase-style commands
USE randData
SET ORDER TO iData
GO TOP
LIST NEXT 10  && First 10 
SKIP 81
LIST NEXT 10  && Last 10
CLOSE ALL
 
&& Browse sorted data using SQL DML commands
SELECT * ;
  FROM randData ;
  ORDER BY iData DESCENDING

Output of the Data handling program.

[edit] ODBC access using SQL passthrough

&& Connect to an ODBC data source
LOCAL nHnd
nHnd = SQLCONNECT ("ODBCDSN", "user", "pwd")
 
&& Execute a SQL command
LOCAL nResult
nResult = SQLEXEC (nHnd, "USE master")
IF nResult < 0
  MESSAGEBOX ("MASTER database does not exist!")
  RETURN
ENDIF
 
&& Retrieve data from the remote server and stores it in
&& a local data cursor
nResult = SQLEXEC (nHnd, "SELECT * FROM authors", "QAUTHORS")
 
&& Update a record in a remote table using parameters
LOCAL cAuthorID, cAuthorName
cAuthorID = "1001"
cAuthorName = "New name"
nResult = SQLEXEC (nHnd, "UPDATE authors SET auth_name = ?cAuthorName WHERE auth_id = ?cAuthorID")
 
&& Close the connection
SQLDISCONNECT(nHnd)

[edit] Beta code names

• VFP 3 - Taz
• VFP 5 - RoadRunner
• VFP 6 - Tahoe
• VFP 7 - Sedona
• VFP 8 - Toledo
• VFP 9 - Europa
• VFP Next - Sedna

[edit] References

[edit] External links

[edit] Microsoft pages

• Main Visual FoxPro Microsoft page
• MSDN FoxPro support board
• VFP's online help
• Microsoft VFP 9 support
• Visual FoxPro Downloads page

[edit] Other pages

The external links in this article may not follow Wikipedia's content policies or guidelines. Please improve this article by removing excessive or inappropriate external links.

• Visual FoxPro Wiki A repository of FoxPro information (written in VFP)
• A site devoted to the history of FoxPro
• FoxPro Summary FoxPro resources and references
• Universal Thread - Online support resource
• Using Win32 (WinAPI) functions in Visual FoxPro
• VFPx A Visual FoxPro Community effort to create open source add-ons for VFP 9.0
• Foxite.com Visual Foxpro experts forum