Monthly Archives: October 2011

Announcing The Microsoft Roslyn CTP

The Roslyn team has announced general availability of the Roslyn CTP!

The official launch is at, and there were a number of blogs to publicize the availability broadly (soma, ericli, vsteam, vbteam, c#faq) and across twitter.

This release marks a significant step to the new way of thinking of compilers, and the agility that is now possible with language innovation, IDE tooling, and powering the ecosystem. The C# and VB compilers are no longer black boxes – something we put source text into, do some magic on, and get an assembly out.  All that rich information about code is no longer thrown away, but is now exposed as a full-fidelity object model that can be easily consumed by all.  In addition, it was released a preview of the first-ever Interactive window for C# that contains full IDE support – including IntelliSense and even automatically detecting missing using directives.

How to get started:

  • Download the CTP.  The CTP installs on Visual Studio 2010 SP1 and can be safely installed side-by-side with Visual Studio 11.
  • Go to Start -> All Programs ->  Microsoft Codename Roslyn CTP -> Getting Started to launch the entry point into all the documentation, samples, and tools.
  • Read the Roslyn Project Overview for a good overview of the project.
  • Learn from the rich samples included (paste as C#/VB, refactorings, code analysis, and code generation tools).
  • Run the walkthroughs to learn about the Compiler APIs, the Services API, or using the Interactive window.
  • For those of you that aren’t extension writers, download the CTP to try out the Interactive window and use the Copy Paste C#/VB extensions that were built to help with your daily work now!

The release includes the following features:

  • Visual Studio Project Templates
    These project templates help you get started using the Roslyn APIs and building new Visual Studio extensions using the C# or VB APIs.
  • Reference Assemblies
    The Roslyn assemblies can be added to projects via the Add Reference dialog.
  • Interactive Window
    A new tool window called C# Interactive is available in Visual Studio by invoking View -> Other Windows -> C# Interactive from the menu. You can explore by either executing snippets of code in the C# Interactive tool window, or cumulatively building up execution context as you experiment.
  • Script File Editing Support
    C# Script (.csx) files allow top-level statements much like the C# Interactive window. You can create a new C# Script file by invoking File -> New File -> Script -> Visual C# Script from the Visual Studio menu. In addition to typing directly into the tool window, you can also select code in C# and C# Script (.csx) files and invoke "Execute in Interactive" or "Copy to Interactive" from the context menu. C# Script editing features like IntelliSense are powered by the Roslyn Language Service.

Please keep in mind that this is only a technology preview, and it’s not done yet! The primary goal of this CTP is to gather feedback on the public APIs and give an early look at the Interactive window feature. The shape of the APIs are in a fairly stable state, especially the Compiler ones, but there are still a set of known limitations and only a subset of the C# and Visual Basic languages are implemented in the current release.  For a full list of non-implemented language features, see here. The Interactive window is only available for C# at this time, but VB is following shortly.

The Roslyn team looks forward to hearing your feedback on the forums e through Connect.

What Is The .NET Framework 4.5?

According to the .NET Blog, .NET Framework 4.5 is an in-place update that replaces .NET Framework 4.0 (rather than a side-by-side installation). The goal is for .NET 4.5 to be fully backward compatible with applications built for .NET 4.0 (.NET 3.5 and .NET 4.5 will be side-by-side).

One of the first things you’ll notice about .NET 4.5 is the version number of the CLR (4.0.30319) is the same as .NET 4.0; this is the practice used by other in-place updates. (read more)

In fact, if you compare a system with .NET 4.5 with a system with .NET 4.0 you’ll see that 4.5 is just an update to 4.0:

Registry key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full
Value .NET 4.0 .NET 4.5
Version 4.0.30319 4.5.40805
CBS 1 1
TargetVersion 4.0.0 4.0.0
Install 1 1
Servicing 0 0
Release   368485
InstallPath C:\Windows\Microsoft.NET\Framework64\v4.0.30319\ C:\Windows\Microsoft.NET\Framework64\v4.0.30319\

One of the major additions to the framework is the support for the Task-based Asynchronous Pattern. All classes with asynchronous APIs have be augmented with a Task-based asynchronous API.

Task exception handling has also changed in .NET 4.5 to accommodate the new async keywords in C# and VB. (read more)

Internet Explorer 10 User Agent Strings On Windows 8 64bit

Internet Explorer 10 is the web browser Microsoft is delivering with Windows 8.

According to its different usages and modes, its user agent string is as follows:

Application Environment 32/64 bit User Agent String
Internet Explorer Metro - Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.2; Win64; x64; Trident/6.0)
Javascript Application Metro - Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.2; Trident/6.0;)
C#/VB Application Metro 32bit Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.2; WOW64; Trident/6.0)
C#/VB Application Metro 64bit Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.2; Win64; x64; Trident/6.0)
Internet Explorer Desktop 32bit
Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.2; WOW64; Trident/6.0)
Internet Explorer Desktop 64bit(1) Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.2; Win64; x64; Trident/6.0)
WPF Application Desktop 32bit Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.2; WOW64; Trident/6.0; .NET4.0E; .NET4.0C; Tablet PC 2.0; .NET CLR 3.5.30729; .NET CLR 3.0.30729; .NET CLR 2.0.50727; Zune 4.7; InfoPath.3)
WPF Application Desktop 64bit Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.2; Win64; x64; Trident/6.0; .NET4.0E; .NET4.0C; Tablet PC 2.0; .NET CLR 3.5.30729; .NET CLR 3.0.30729; .NET CLR 2.0.50727; Zune 4.7; InfoPath.3)
(1) Needs to be enabled for each security zone.

Analyzing the above table I conclude that:

  1. Metro Internet Explorer is always a 64bit application on 64bit Windows 8.
  2. Javascript Metro Style Applications don’t announce if they are 32bit or 64bit.
    1. They look like they are running on a 32bit Windows 8.
  3. Desktop Internet Explorer retains the same behavior introduced with Internet Explorer 8.
  4. Metro Style C#/VB Applications hosting the web browser (WebView control) exhibit the same behavior as Internet Explorer.
  5. Desktop WPF Applications hosting the web browser (WebBrowser control) retain the same behavior introduced with Internet Explorer 8.