Microsoft ASP.NET 4.0

New Features in ASP.NET 4.0

ViewState Control Enhancements

One of the major drawbacks of ASP.NET Webforms is ViewState, which can add significantly to the page size and slow performance. While initially you could set the EnableViewState property to true or false, all the controls, by default inherit and so if you set it at the control level, the behavior was inconsistent. However, with ASP.NET 4.0, the new ViewStateMode property helps to determines every control whether the ViewState should be enabled, disabled, or inherited.

Webform Routing

Routing is a feature in ASP.NET 4.0 that enables you to use URLs to map specific resources. These URLs can then become more descriptive and user friendly. Here is an example of an URL that is descriptive: http://server/mywebapplication/Students/View/NewStudents

Reading the routing information in an ASP.NET page is as simple as the following code:

String data = Page.RouteData.Values["Item"] as string;

ASP.NET Routing was originally developed as part of ASP.NET MVC but factored out into its own assembly (System.Web.Routing) as it is useful beyond the bounds of MVC. It is used in ASP.NET Dynamic Data for example and it’s even possible to use it in webforms with a bit of work.

In ASP.NET 4.0 all the necessary components to use ASP.NET Routing are inbuilt. These include theIRouteHandler implementation (PageRouteHandler class) that serves up the right IHttpHandler to service the request and a couple of expression builders to help capture parameters from routed requests and also generate route URLs. You simply need to set up your route patterns in Application_Start() as you do for ASP.NET MVC.

SEO Enhancements

In addition to Webforms Routing, there are a couple of minor additions to ASP.NET 4.0 to make it easier to set the Keywords and Description meta tags on a page. The page class in ASP.NET 4.0 now has two new properties, namely, Keywords and Description. These can be set either in markup code or from the code behind so that you can generate the meta tags dynamically.

Simplified Web.Config File: One of the most striking features in ASP.NET 4.0 is web.config minification – a feature that allows you to have a web.config file that is much smaller in size with fewer configuration elements compared to what we used to have in the earlier versions of ASP.NET. Most of the configuration elements now have been moved to the machine.config file resulting in a minified web.config file for your applications. Your applications can easily inherit the settings specified in the machine.config file. So, you can have a web.config file that is either empty or, much smaller in size.

Caching Enhancements: Until now, any page output is stored in memory in a private area of the ASP.NET cache. However, in the long run, the output cache puts additional pressure on the web server by consuming memory and generating frequent updates to the cache object. In ASP.NET 4.0, the output caching subsystem gives an opportunity to the developers to store page responses outside the ASP.NET worker process, by fully supporting the provider model.

Session State Improvements: In ASP.NET 4.0 you can use compression for out of process session state providers.

Better Control over ClientID’s of Controls: ASP.NET 4.0 provides support for customizing the Client ID that is generated by the ASP.NET engine for the controls in the web pages of your application. The new ClientIDMode property is now available for setting the client ID at either the Page, Application or Control levels. Note that you can set the ClientIDMode for any controls on your web page. You can even set the ClientIDMode for your web page.

Support for Performance Monitoring: Performance Monitoring is an area where ASP.NET 4.0 is way ahead from its earlier counterparts. Previously there was no direct way to analyze or monitor application performance. You can now use ASP.NET 4.0 to monitor resource functionality . ASP.NET 4.0 provides support for monitoring the performance of individual applications inside a single worker process. This feature provides a more granular view of the resources being consumed by your application.