New Features in ASP.NET 4.0

Joydip Kanjilal, Software Consultant and Author

ASP.NET is  the most popular Web application framework for

programmers to build dynamic websites and services. The language-neutral,

interoperable server side technology runs on top of the managed environment of .NET's

CLR and within the context of a web server like IIS, and allows creation,

execution, and deployment of scalable Web Apps and services seamlessly. To work

with ASP.NET 4.0, you need to have Visual Studio 2010 installed on your system.

You can download  Beta 2 of the same from here: http://tinyurl.com/o949y9  Let's

take a look at the new features of ASP.NET 4.0.

State management improvements



In ASP.NET 4.0, there has been marked improvements in Cache, Session and

ViewState. The  Cache API now allows you to store data in any of the following

cache storages; disk-based output caches -used to store cache data in disk,

custom object caches -used to store cache data using custom cache providers,

distributed object caches -used to store cache data in a separate server and

Cloud-based object caches -used to store cache data in Cloud databases.  Now you

can use ASP.NET 4.0 Cache API to design and implement your custom cache storage

provider too. You can also configure your custom cache provider easily in your

application's web.config file. Here's an example:

There has also been a marked improvement in ViewState in

ASP.NET 4.0. You can now use the ViewStateMode property -a new property
introduced for all controls in ASP.NET 4.0, to determine whether or not
ViewState should be enabled for a particular control in your webform. This gives

your better control and flexibility on the ViewState.

Enhancements to ASP.NET data presentation controls



In ASP.NET 4.0, the LayoutTemplate of the ListView control is optional. You

can now use the ItemTemplate of the ListView control to display and manage your

data. Here is an example:

ClientIDMode="Predictable">






Customer Code:


/>







Customer Name:


/>

Another improvement in ASP.NET 4.0 is the introduction of a

new property called RepeatLayout in the RadioButtonList and CheckBoxList

controls.

Support for performance monitoring



You can turn on application resource monitoring feature for your

applications by using the following configuration in the aspnet.config file:

It should be noted that when the

appDomainResourceMonitoring feature is enabled in your application, two new

performance counters are distinctly visible in the "ASP.NET Applications

Performance" category. These include '% Managed Processor Time' and 'Managed

Memory Used'.

Enhanced control over ControlIDs of controls



You can have better control over the controlIDs of your data controls in the

web page. ASP.NET 4.0 introduces a new property called ClientIDMode for each and

every control. This property can have any one of the following possible values;

AutoID, Inherit, Static, and Predictable. Note that you can set the ClientIDMode

property at the page, application and even at the control levels. The following

code snippet illustrates how you can set the ClientIDMode at the application

level:

The following code snippet illustrates how you can set the

ClientIDMode for a TextBox control in your markup code:

runat="server" ClientIDMode="Static" />

To set the ClientIDMode property at the control level, you
can use the foollowing syntax:

ID="GridView1" AutoGenerateColumns="False" ClientIDMode="AutoID">

And, here is how you can set the ClientIDMode property at

the page level:

<%@ Page Language="C#"

AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default"

ClientIDMode="Predictable" %>



Support for Routing

Routing was initially introduced in ASP.NET MVC Framework.

With ASP.NET 4.0, Routing has been made a feature of ASP.NET. You can use

Routing to map specific resources using user friendly URLs. Note that support

for Webform Routing in ASP.NET 4.0 is provided by the System.Web.Routing

namespace.

SEO enhancements



In ASP.NET 4.0 there are two new properties in your Page class -Keywords and

Description, that you can use to optimize searches. The following code

illustrates how you can set these properties using C# code in the code behind

file for your web form:

public partial class TestWebForm :

System.Web.UI.Page



{


protected void Page_Load(object sender, EventArgs e)


{


Page.Keywords = "ASP.NET 4.0 Programming by Joydip Kanjilal";

Page.Description = "PC Quest";



}


}

It is also possible to achieve the same using markup code.

Here is an example:

Simplification of Web.Config file



The web.config file in ASP.NET 4.0 is much simplified. Most of the

configuration elements have now been moved to the machine.config file. This

results in reduced size of the web.config file. You can now specify the

framework that your application is designed to be targeted at. To do this, you

can simply specify the following in your application's web.config file:

About the Author : Joydip Kanjilal  has over 12

years of industry experience in IT with more than 6 years in Microsoft .NET &

its related technologies.  Joydip has authored several books on ASP.NET.