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"VFP" redirects here. For the floating-point extension of ARM processors, see ARM architecture#VFP.
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.
Recent historyIn 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. 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:
Version informationOperating system compatibility
Information on executable files
Code samplesHello World example: MESSAGEBOX("Hello World") ObjectloForm = 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 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 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) Beta code names
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Mercedes Car
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