Multi-Targeting Support - Orcas New Features

Hi,

This blog post summarizes the new features of ASP.Net 3.5 and VS 2008 IDE.

Below are the new features been introduced.

§ VS 2008 Multi-Targeting Support

§ VS 2008 JavaScript Intellisense

§ VS 2008 JavaScript Debugging

§ VS 2008 Code Editing Improvements

§ VS 2008 Nested Master Page Support - - Nothing to add. Read Post.

§ VS 2008 Web Designer and CSS Improvements

§ VS 2008 Vertical Split View Support - Nothing to add. Read Post.

§ VS 2008 ASP.NET AJAX Control Extenders

§ ASP.NET ListView Control (Part 1: Building a Product Listing Page with Pure CSS)

§ ASP.NET AJAX in .NET 3.5 and VS 2008

Before we go further let’s have a quick view.

Compatibility - From VS 2005 to VS 2008 and .NET Framework 2.0 to 3.5?

Though .NET Framework 3.5 is a super compatible upgrade from .NET 2.0, it does not require you to change any code in order to target the new framework version. Only non-breaking modifications to existing .NET assemblies have been made in the .NET 3.5 release, and wherever possible added new features in separate assemblies to minimize the chance of breaking changes.

Also no project model or build changes have been made with VS 2008. Both the "web site" and "web application project" models will be fully supported going forward.

Multi-Targeting Support

Here I have been putting major points on Multi Trageting. For other details, how it works please folow the below link.

Reference: http://weblogs.asp.net/scottgu/archive/2007/06/20/vs-2008-multi-targeting-support.aspx

"Multi-Targeting" - which means that Visual Studio will now support targeting multiple versions of the .NET Framework, and developers will be able to start taking advantage of the new features Visual Studio provides without having to always upgrade their existing projects and deployed applications to use a new version of the .NET Framework library.

When we choose a particular framework - The IDE will update its compilers and feature-set to match this. Among other things, this means that features, controls, projects, item-templates, and assembly references that don't work with that version of the framework will be hidden, and when you build your application you'll be able to take the compiled output and copy it onto a machine that only has an older version of the .NET Framework installed, and you'll know that the application will work.

So why use VS 2008 if you aren't using the new .NET 3.5 features?

You might be wondering: "so what value do I get when using VS 2008 to work on a ASP.NET 2.0 project versus just using my VS 2005 today?" Well, the good news is that you get a ton of tool-specific value with VS 2008 that you'll be able to take advantage of immediately with your existing projects without having to upgrade your framework/ASP.NET version. A few big tool features in the web development space I think you'll really like include:

1. JavaScript intellisense

2. Much richer JavaScript debugging

3. Nested ASP.NET master page support at design-time

4. Rich CSS editing and layout support within the WYSIWYG designer

5. Split-view designer support for having both source and design views open on a page at the same time

6. A much faster ASP.NET page designer - with dramatic perf improvements in view-switches between source/design mode

7. Automated .SQL script generation and hosting deployment support for databases on remote servers

You'll be able to use all of the above features with any version of the .NET Framework - without having to upgrade your project to necessarily target newer framework versions. I'll be blogging about these features (as well as the great new framework features) over the next few weeks.

Can an upgrade of an existing project to .NET 3.5 later is supported?

· Simply right-click on the project in the solution explorer and pull up its properties page.

· Change the "Target Framework" dropdown to select the version of the framework you want the project to target. Doing this will cause VS to Automatically Update Compiler Settings And References for the project to use the correct framework version. i.e it will add below.

· Will by default add some of the new LINQ assemblies to your project.

· As well as add the new System.Web.Extensions assembly that ships in .NET 3.5 which delivers new ASP.NET controls/runtime features and provides built-in ASP.NET AJAX.

What about .NET 1.0 and 1.1?

Unfortunately the VS 2008 multi-targeting support only works with .NET 2.0, .NET 3.0 and .NET 3.5 - and not against older versions of the framework. The reason for this is that there were significant CLR engine changes between .NET 1.x and 2.x that make debugging very difficult to support. In the end the costing of the work to support that was so large and impacted so many parts of Visual Studio that we weren't able to add 1.1 support in this release.

VS 2008 does run side-by-side, though, with VS 2005, VS 2003, and VS 2002. So it is definitely possible to continue targeting .NET 1.1 projects using VS 2003 on the same machine as VS 2008.

Hope this helps.

Thanks & Regards,

Arun Manglick || Tech Lead