ASP.NET Page and Controls Framework

The ASP.NET page and controls framework is a programming framework that runs on a Web server to dynamically produce and render ASP.NET Web pages. ASP.NET Web pages can be requested from any browser or client device, and ASP.NET renders markup (such as HTML) to the requesting browser. As a rule, you can use the same page for multiple browsers, because ASP.NET renders the appropriate markup for the browser making the request. However, you can design your ASP.NET Web page to target a specific browser, such as Microsoft Internet Explorer 6, and take advantage of the features of that browser. ASP.NET supports mobile controls for Web-enabled devices such as cellular phones, handheld computers, and personal digital assistants (PDAs).

ASP.NET Web pages are completely object-oriented. Within ASP.NET Web pages you can work with HTML elements using properties, methods, and events. The ASP.NET page framework removes the implementation details of the separation of client and server inherent in Web-based applications by presenting a unified model for responding to client events in code that runs at the server. The framework also automatically maintains the state of a page and the controls on that page during the page processing life cycle.

The ASP.NET page and controls framework also enables you to encapsulate common UI functionality in easy-to-use, reusable controls. Controls are written once, can be used in many pages, and are integrated into the ASP.NET Web page that they are placed in during rendering.

The ASP.NET page and controls framework also provides features to control the overall look and feel of your Web site via themes and skins. You can define themes and skins and then apply them at a page level or at a control level.

In addition to themes, you can define master pages that you use to create a consistent layout for the pages in your application. A single master page defines the layout and standard behavior that you want for all the pages (or a group of pages) in your application. You can then create individual content pages that contain the page-specific content you want to display. When users request the content pages, they merge with the master page to produce output that combines the layout of the master page with the content from the content page.