Visual FoxPro

Visual FoxPro is a programming language that was developed by Microsoft. It is a data-centric and procedural programming language with object-oriented programming (OOP) features. It was derived from FoxPro (which was itself descended from 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 December 2004¹ and updated in October 2007 with the SP2 patch, was the final version of the product. Support ended in January 2010 and extended support in January 2015.

Visual FoxPro is a programming language that was developed by Microsoft. It is a data-centric and procedural programming language with object-oriented programming (OOP) features. It was derived from FoxPro (which was itself descended from 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 December 2004 and updated in October 2007 with the SP2 patch, was the final version of the product. Support ended in January 2010 and extended support in January 2015. ==Features== ===Programming language=== The Visual FoxPro programming language is a high-level general-purpose procedural language. As such it is broadly similar to BASIC, Pascal and Python. Its features include: Structured programming constructs for branching ( IF / ELSE / ENDIF , DO CASE / ENDCASE ) and looping ( FOR / ENDFOR , DO WHILE / ENDDO ). Loosely-typed variables. Ability to call functions (both built-in and programmer-defined), with parameters passed by value or reference. Support for object-oriented programming (OOP), including inheritance, encapsulation and polymorphism. Structured Query Language (SQL). SQL code can be used interchangeably with native FoxPro code. ====Code samples==== Display text in a standard message box MESSAGEBOX('Hello World') Function call f = Factorial(10) Function definition FUNCTION Factorial(n) LOCAL i, r r = 1 FOR i = n TO 1 STEP -1 r = r * i ENDFOR RETURN r ENDFUNC ===IDE=== Visual FoxPro has an extensive integrated development environment (IDE), with tools to assist in application development, including: A command window into which the developer can enter commands for immediate execution. The output of the commands, if any, is displayed on the background screen or in an active window. Visual design tools (also called power tools). These allow the developer to visually design components such as class definitions, forms, reports, labels and menus. These tools provide an alternative to writing code by hand. In earlier versions of FoxPro, tools similar to these generate program code which can then be edited by the programmer. In Visual FoxPro, on the other hand, the tools store details of the design in tables which VFP interprets at run time to produce the required components . A program editor which supports syntax highlighting, automatic indentation and code completion. These are implemented via Microsoft's Intellisense technology. A debugger which allows the developer to step through program code, to set breakpoints to interrupt program execution, to examine variables and to view the call stack. ===Database=== As well as being a tool for application development, Visual FoxPro serves as a database management system. The database is tightly integrated with the programming language and the IDE. In earlier versions, as well as in other Xbase-based systems, each table in the database is held in its own physical file (along with associated files which hold indexes and memo [free-text] fields). The tables are independent of each other. The database does not store information about the relationships in the data, this being defined within the application. The data is stored in the DBF file format. Visual FoxPro also supports this model, but does so mainly to maintain backward compatibility. It also introduces the concept of a "database container" (DBC). Here, the tables continue to be held in separate DBF files, but these are grouped in a container which stores information about the relationships, thus having some of the characteristics of a true relational database management system (RDBMS). It also supports primary keys, triggers and built-in validation rules. The IDE includes interactive tools for creating and maintaining databases and tables, and for retrieving and editing data. These actions can also be implemented in program code, using either native FoxPro commands and functions or SQL. ====Code samples==== Place customers with overdue balances into a temporary table FoxPro native code CREATE CURSOR Overdue (Company C(10), Balance N(5), Due D) USE Customer SCAN IF Due ===Notes=== MSDN FoxPro support board VFP's online help

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