New CSharp Language features 3.0 and 4.0: Difference between revisions

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* see http://soumya.wordpress.com/2009/06/12/new-features-in-c-part-ii-c-3-0/
* see http://soumya.wordpress.com/2009/06/12/new-features-in-c-part-ii-c-3-0/


* Automatic Properties
==== Implicitly Typed Local Variables (aka 'Local Variable Type Inference') ====
** used already in the web server for conference backend. saves writing dumb code
* At first glance this feature looks like it does what the 'dreaded' VARIANT Type of Visual Basic 6 does, where it results in ''late-bound Type Inference'' which can cause very difficult-to-spot errors at runtime.
* Object Initializer
* ''However'', Implicitly Typed Local Variables result in ''early-bound strongly-typed'' code, which is way better as its VB 6 'colleague' as it can not cause those errors at run-time!
** used by ext.net which is used by the web server for conference backend.
* Only works for ''local variables in a method'' (that is, not for Class Fields or Method Arguments).
* Collection Initializers, Dictionary Initializers
* Usage
* Extension Methods
** Use new <code>var</code> keyword for the declaration of such variables.
* LINQ
** ''Should not be over-used'' as the source code is less explicit then when the Type it holds is stated explicitly.
* Anonymous Types and Implicit Type Variables
** Can be a time saver for declaration of long types, esp. Generic ones; there it fine to be used and actually can result in easier-to-read code.
* Lambda Expressions
* '''Details: [http://www.danielmoth.com/Blog/local-variable-type-inference-in-c-30.aspx]'''
* Partial Methods
 
==== Anonymous Types ====
 
 
==== Auto-implemented Properties (aka 'Automatic Properties') ====
* used already in the web server for conference backend. saves writing dumb code
 
==== Object Initializers ====
* used by ext.net which is used by the web server for conference backend.
 
==== Collection Initializers, Dictionary Initializers ====
 
==== Partial Methods ====
* Available in Partial Classes only.
 
==== Extension Methods ====
 
==== Lambda Expressions ====
* Replace Anonymous Methods, which were new in C# 2.0.
 
==== LINQ ====
 
 


=== C# 4.0 ===
=== C# 4.0 ===
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* see http://soumya.wordpress.com/2009/06/12/new-features-in-c-part-iii-c-4-0/
* see http://soumya.wordpress.com/2009/06/12/new-features-in-c-part-iii-c-4-0/


* Named and Optional Parameters
==== Named Parameters ====
** this looks most interesting for us
* This looks most interesting for us.
* Dynamic Support
 
* Variance
==== Optional Parameters ====
* COM Interop
* This looks very interesting for us, too.
 
==== Dynamic Support ====
 
==== Variance ====
 
==== COM Interop ====
* Probably not interesting for us as the OpenPetra Client should stay platform-independent (COM is available only on Windows OS's).
* Could ''potentially'' be useful for optional plug-ins for the OpenPetra Client that would need COM to fulfill their roles, though. Obviously those plug-ins would work on only Windows OS's then.
 


== Mono and new C# features ==
== Mono and new C# features ==
TODO
TODO

Revision as of 14:16, 26 October 2011

New features

C# 3.0

Implicitly Typed Local Variables (aka 'Local Variable Type Inference')

  • At first glance this feature looks like it does what the 'dreaded' VARIANT Type of Visual Basic 6 does, where it results in late-bound Type Inference which can cause very difficult-to-spot errors at runtime.
  • However, Implicitly Typed Local Variables result in early-bound strongly-typed code, which is way better as its VB 6 'colleague' as it can not cause those errors at run-time!
  • Only works for local variables in a method (that is, not for Class Fields or Method Arguments).
  • Usage
    • Use new var keyword for the declaration of such variables.
    • Should not be over-used as the source code is less explicit then when the Type it holds is stated explicitly.
    • Can be a time saver for declaration of long types, esp. Generic ones; there it fine to be used and actually can result in easier-to-read code.
  • Details: [1]

Anonymous Types

Auto-implemented Properties (aka 'Automatic Properties')

  • used already in the web server for conference backend. saves writing dumb code

Object Initializers

  • used by ext.net which is used by the web server for conference backend.

Collection Initializers, Dictionary Initializers

Partial Methods

  • Available in Partial Classes only.

Extension Methods

Lambda Expressions

  • Replace Anonymous Methods, which were new in C# 2.0.

LINQ

C# 4.0

Named Parameters

  • This looks most interesting for us.

Optional Parameters

  • This looks very interesting for us, too.

Dynamic Support

Variance

COM Interop

  • Probably not interesting for us as the OpenPetra Client should stay platform-independent (COM is available only on Windows OS's).
  • Could potentially be useful for optional plug-ins for the OpenPetra Client that would need COM to fulfill their roles, though. Obviously those plug-ins would work on only Windows OS's then.


Mono and new C# features

TODO

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