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Professional ASP.NET 3.5 in C# and Visual Basic Part 64

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Professional ASP.NET 3.5 in C# and Visual Basic Part 64. Building on the revolutionary ASP.NET 2.0 release, ASP.NET 3.5 adds several key new developer features including AJAX, LINQ, and a new CSS designer in Visual Web Developer 2008. The dramatic reduction in code that developers realized from the more than 50 new server controls in ASP.NET 2.0 now allows developers the time to make their applications more interactive with AJAX, to work with data in their preferred language with LINQ, and to build visually attractive and consistent standards-based sites with CSS. . | Introduction to the Provider Model The ASP.NET provider model is an important framework to understand as you build your applications. The ASP.NET provider model was a major change introduced in ASP.NET 2.0 so you probably already know that ASP.NET is a way to build applications for the Internet. For the Internet means that an application s display code travels over HTTP which is a stateless protocol. ASP.NET works with a disconnected architecture. The simple nature of this model means that requests come in and then responses are sent back. On top of that ASP.NET does not differentiate one request from another. The server containing an ASP.NET application is simply reacting to any request thrown at it. This means that a developer building a Web application has to put some thought into how users can remain in context between their requests to the server as they work through the application. Keeping a user in context means recording state the state of the user to some type of data store. This can be done in multiple ways and no one way is the perfect way. Rather you have to choose one of the available methods. You can read about maintaining state in an ASP.NET application in Chapter 22. State can be stored via multiple methods some of which include Application State Session State The Cache Object You use all these methods on the server but you can also employ your own custom methods such as simply storing state in a database using your own custom schema. It is also possible to write state Chapter 12 Introduction to the Provider Model back to the clients either directly on their computers or by placing state in the HTML output in the response. Some of these methods include Cookies Querystrings Hidden Fields ViewState Understanding the Provider These methods work rather well but most of them are rudimentary and have short life spans. ASP.NET 3.5 includes a handful of systems such as the new membership and role management systems that handle state for users between .