Each event-handler is usually bound to a specific object or control on a form. Many visual programming environments will even provide code templates for event-handlers, so the programmer only needs to provide the code that defines the action the program should take when the event occurs. Once the user interface is substantially complete, the programmer can add event-handling code to each control as required. The programmer can therefore concentrate on issues such as interface design, which involves adding controls such as command buttons, text boxes, and labels to standard forms (a form represents an application's workspace or window). Visual Basic, Visual C++ and Java are examples of such languages.Ī visual programming IDE such as VB.Net provides much of the code for detecting events automatically when a new application is created. Virtually all object-oriented and visual languages support event-driven programming. The idea is an extension of interrupt-driven programming of the kind found in early command-line environments such as DOS, and in embedded systems (where the application is implemented as firmware).Įvent-driven programs can be written in any programming language, although some languages(Visual Basic for example) are specifically designed to facilitate event-driven programming, and provide an integrated development environment (IDE) that partially automates the production of code, and provides a comprehensive selection of built-in objects and controls, each of which can respond to a range of events. An event-driven application is designed to detect events as they occur, and then deal with them using an appropriate event-handling procedure. Event-driven programming is a programming paradigm in which the flow of program execution is determined by events - for example a user action such as a mouse click, key press, or a message from the operating system or another program.

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