What is new in asp.net 4.0

The following sections describe new features in ASP.NET core services, Web Forms, Dynamic Data, and Visual Web Developer.
ASP.NET Core Services

ASP.NET introduces several features that improve core ASP.NET services, Web Forms, Dynamic Data, and Visual Web Developer. For more information, see What’s New in ASP.NET and Web Development.
ASP.NET Web Forms

Web Forms has been a core feature in ASP.NET since the release of ASP.NET 1.0. Many enhancements have been made in this area for ASP.NET 4, including the following:

    *       The ability to set meta tags.
    *       More control over view state.
    *       Easier ways to work with browser capabilities.
    *       Support for using ASP.NET routing with Web Forms.
    *       More control over generated IDs.
    *       The ability to persist selected rows in data controls.
    *       More control over rendered HTML in the FormView and ListView controls.
    *       Filtering support for data source controls.

Dynamic Data

For ASP.NET 4, Dynamic Data has been enhanced to give developers even more power for quickly building data-driven Web sites. This includes the following:

    *       Automatic validation that is based on constraints defined in the data model.
    *       The ability to easily change the markup that is generated for fields in the GridView and DetailsView controls by using field templates that are part of your Dynamic Data project.

Visual Web Developer Enhancements

The Web page designer in Visual Studio 2010 has been enhanced for better CSS compatibility, includes additional support for HTML and ASP.NET markup code examples, and features a redesigned version of IntelliSense for JScript. In addition, two new deployment features called Web packaging and One-Click Publish make deploying Web applications easier.