C# 4.0 – What’s new?
Venketash (Pat) Ramadass
Systems Architect & Managing Director
emediaIT
Email Address: pat.ramadass@emediait.com
Blog: http://patramadass.emediait.com

Before all of that...
Who here is primarily using VS 2003 and .NET 1.1?

Who here is primarily using VS 2005 and .NET 2.0?

Who here is primarily using VS 2008 and .NET 3.5?

◦ What features are you using?
 WPF, WCF, WF LINQ etc?
Who has played with VS 2010 CTP?

◦ Available for download

Items we are going to Cover...
What’s new in VS 2010

What’s new in .NET 4.0

What’s new in c# 4.0

Questions

Note: All of these technologies are still new and are

still maturing through CTPs followed by Betas/RCs

What’s new in VS 2010

What’s new in VS 2010 – General
.NET Framework 4.0

Tooling and Framework advancements that take advantage

of the latest trends including:
◦ Cloud Development
 Windows Azure and similar
◦ Parallel Computing
 Taking advantage of multi-core systems
Updated editor built in WPF

◦ Graphical view of source files, code coverage etc
Simplified and more powerful TDD

◦ Consume first declare second

What’s new in VS 2010 – TDD

What’s new in VS 2010 – Web Development
Full inclusion of:

◦ ASP .NET MVC
◦ JQuery
◦ Sliverlight
Improved JavaScript IntelliSense engine

Improved SharePoint tools and project templates

◦ VS 2010 Tools for SharePoint
 Replacement for SharePoint Designer

What’s new in VS 2010 – SharePoint
Development
New Project Templates

 Import content using WSP Import

What’s new in VS 2010 – SharePoint
Development

What’s new in VS 2010 – Other
Windows 7 Development

◦ Updates to MFC to support Windows 7, including new UI elements
Office Business Application Development

◦ Build Office client applications that span multiple versions and target
32-bit/64-bit as using a single deployment package
“Dublin” and “Oslo” in pipeline

◦ “Dublin” will provide enhanced server capabilities, building on IIS for
WCF and WF application hosting
◦ “Oslo” is a modelling platform for model-driven applications
 “M” Language – Authoring domains textually
 Quadrant – Tool for authoring domains visually
 Library of pre-built domain models

What’s new in VS 2010 – Team System -
Rosario
Who here uses VSTS and/or VSTFS?

◦ What features/aspects do you use?
Highlights include:

◦ “Democratizing” Application Lifecycle Management
 Architectural consistency
 Limiting “No-Repro” bugs
◦ Improved modelling
 Technical and non-technical users
◦ Improved QA/Test Planning and execution
 Microsoft Test Runner
◦ Snapshot of system data
◦ Partial/full video capture
 Test Impact View

What’s new in VS 2010 – Test Impact View

What’s new in VS 2010 – Team System –
Architecture Explorer

What’s new in .net 4.0

What’s new in .net 4.0 – Some Highlights
Updates to BCL – Base Class Lilbrary

Code Contracts

◦ System.Diagnostics.Contracts
◦ Language agnostic
◦ Specify Pre-conditions, post-conditions and objects
invariants
Parallel Extensions

◦ Task Parallel Library, Parallel LINQ

What’s new in .net 4.0 – Some Highlights
BigInteger

◦ System.Numerics.BigInteger
◦ Supports all standard Integer operations
Compression Improvements

◦ Removed 4GB stream limit
Various WCF and WF enhancements

ASP.NET

◦ Static Client Ids
◦ Chart Control

What’s new in c# 4.0

What’s new in c# 4.0
Onto why we’re actually here...

◦ Dynamic Lookup
◦ Named and Optional Arguments
◦ Features for COM Interop
◦ Variance

What’s new in c# 4.0 – Dynamic Lookup
New dynamic type

Resolution of method calls or field accesses is

deferred until runtime
Allows for calling or accessing identical methods

or properties across unrelated objects

What’s new in c# 4.0 – Dynamic Lookup
Demo

What’s new in c# 4.0 – Dynamic Lookup
DLR – Dynamic Language Runtime is underlying

mechanism
This could be done before, using reflection or

interfaces etc, but it would require much more
work
Convenience comes with drawbacks

◦ Performance
 Reflection is used underneath
◦ Only have runtime checking

What’s new in c# 4.0 – Named and Optional
Arguments
Historically multiple overloads were required to

achieve this type of thing in c#
◦ Named parameters were never possible
Now this can be done using the optional argument

syntax in a single constructor

What’s new in c# 4.0 – Named and Optional
Arguments Demo

What’s new in c# 4.0 – Features for COM
Interop
Dynamic import allows you to import COM APIs so that

variants are represented using dynamic type instead of
object. Code that looked like...
...could now look like...

What’s new in c# 4.0 – Features for COM
Interop
COM APIs use a lot of ref parameters. In c# 4.0 the

compiler allows you to omit the ref in COM APIs
“No PIAs’ Feature

◦ Ability to compile your application so that it does not
require the Primary Interop Assemblies.
◦ Instead a small portion of the PIA required is put directly
into the program’s assembly

What’s new in c# 4.0 – Variance
Variance is one of those things most of us don’t

often don’t have to think about
There are some cases which you may assume

should work that don’t however.

What’s new in c# 4.0 – Variance
The following example does not work even though

string obviously inherits from object
If it did, the following would have to work, which

goes against type safety

What’s new in c# 4.0 – Variance
There may however be times where you would

want to have this type of thing happening and for
it to happen safely
c# 4.0 allows for covariance and contravariance

through the new out and in keywords

What’s new in c# 4.0 – Covariance and
Contravariance Demo

Conclusion
A lot of great new technologies and tools coming

out very soon
There are some key advancements in both c# and

.net 4.0, so we should all be looking to familiarise
ourselves with them and take advantage when
they are available
Download VS 2010 CTP and go through the

Walkthroughs

References
http://www.microsoft.com/visualstudio/en-

us/products/2010/default.mspx
◦ Visual Studio 2010 main site and CTP download
◦ CTP is in the form of a VHD and some software
expired on it in January 2009. There are
workarounds.
http://channel9.msdn.com/pdc2008/TL26/

◦ Parallel Programming for Managed Developers with
Visual Studio 2010
http://patramadass.emediait.com

◦ This presentation, example code

Questions?