Summary

Summary

• Web applications use Web forms to create a user interface that is presented through an Internet browser on the user s computer.

• The code and resources that respond to events and perform useful tasks reside and run on the Web server hosting the application.

• Because Web applications are distributed between a client and a server, there are five significant differences between programming for the Web and programming for Windows:

  • Web applications use server controls and HTML controls rather than Windows controls.

  • Web applications are displayed in a Web browser rather than in their own window.

  • Web forms are not persistent while displayed. You must preserve persistent data in a state variable during page and control events.

  • Processing occurs on the server, and data is exchanged through a cycle of requests and responses.

  • Web applications are event-driven, and events occur at the application, page, and server control levels.

• Server control events have three types, which occur in the following order:

  • Validation events occur before the page is returned to the server.

  • Cached events are collected while the page is displayed and then processed once the page sends a request to the server.

  • Postback events cause the page to send a request to the server, but their event procedure is processed last in order of events handled.

• The boundaries of a Web application are determined by its folder structure.

• Application boundaries affect the scope of data stored in Application state.

• You use IIS to create root folders for your applications, set application boundaries, and determine the process in which IIS runs your application.