Are C# and .NET versions dependent on each other? - c#

I'm just starting to learn C# and its relationship to .NET. If say I wanted to take advantage of the latest C# language conventions, but wanted to target, say a .NET 2.0 framework, could I do that? Or does using the latest C# mean I have to use the latest .NET?

C# as a language is not dependent on .net framework.
For example: Extension methods is a feature released with C# 3.0 which came along with .Net 2.0.
Extension methods depends on ExtensionAttribute which lives in "mscorlib.dll" which was added in .Net 3.5. But you can use Extension methods in .Net 2.0 given that you provide your own ExtensionAttribute in your library itself. It doesn't needs to be in mscorlib. Refer this question for more info.
As we know async-await is new in C# 5.0 which was released with .Net 4.5, but we can use async-await in .Net 4.0 itself.
Sameway, most of the dependencies of language features can be defined in your own assembly to make it work. So it doesn't need the particular .Net framework version.

you can use features of lastest visual studio editions (2013, 2015), but the code must be according to 2.0 specifications to allow a .NET 2.0 compilation (older versions)

Yes, C# and .Net versions are dependent. According to my understanding C# is a programming language which works using .Net Technology.
Learning C# means learning the basic syntax, which is almost the same in all .Net versions. So for learn c#, it doesn't matter which .Net version you must target. Different .Net versions adds up certain new features or functionality. Any way its better to understand latest .Net version which will help you in projects.

You can use C# features from earlier versions with later versions of .Net, for example, you can use any C# 2.0 feature with .Net 3.5, this does not work the other way arround, so you cannot use .Net 3.5 features with the c# 2.0 compiler.
For more details see: https://msdn.microsoft.com/en-us/library/ff602939(v=vs.110).aspx

C# 6.0 is available in .NET 5.0.
It depends on the CLR. C# 4, 4.5 and 4.5.1 are using the CLR Version 4.

Yes C# is dependent on .net versions. The dependence between the both is on features and technologies provided. Refer following link:
https://msdn.microsoft.com/en-us/library/bb822049%28v=vs.110%29.aspx

Related

If I know .NET 4.0 is installed on a user's machine, can I assume .NET 2.0 is as well?

Pretty self-explanatory question, but here's a bit of context:
My app (C++, unmanaged) has a feature written as a C# app. This feature is only available when we know .NET is installed. So, must I maintain separate versions of this C# application for each framework version we want to support, or will a lowest-common-denominator of .NET 2.0 work (thus, if we detect any framework installed >= 2.0, we know we will be OK)?
Note that I prefer to just maintain a single .NET 2.0 version of our C# app.
You can assume that .net 2.0 apps will run on the 4.0 runtime.
See: http://msdn.microsoft.com/en-us/library/ff602939.aspx
The .NET framework dependencies page for .NET 4 on MSDN says that yes, you can count on it:
You do not have to install previous versions of the .NET Framework or
the CLR before you install the latest version; each version provides
the necessary components.
Yes, if you write and build your application against .Net 2.0, it will work with all versions going forward.
Yes... (.net 2 will work on .net 4)
I met a problem with mixed-mode assemblies like SharpSvn, which needed CLR v.2 to run, while my app was compiled for .NET 4, so we had to install both versions of the framework.
Still I believe it's not your case.
yes it has back compatibility assured , i have done this with .net 3 & 3.5sp1 and they are currently running on .net 4 without any problem.

Using .NET 1.1 libraries in .NET 4.0 applications

Are there any known stability issues when using .NET 1.1 libraries in a .NET 4.0 application?
We have used many .NET 1.0 libraries in different version of framework (any thing between 1.1 to 4.0) and have never experienced any issues. we currently use SQLDataProvider which I think was release a bit after .NET 1.0.
Then again it all depends on the code that is included in those libraries. I would spend some time to look for updated version of those libraries or even alternative, specially something that was written in 2.0 or higher just because of introduction of generics.
but otherwise, do some testing and you should be fine.
Generic answer is NO. You should be able to use .NET 1.1 libraries in a .NET 4.0 project witout any issues. But every library is different. Is it a custom dll? Does it use any COM components?

What is the official marketing name for C# 4?

What is the official marketing name for C# 4?
Apress writes "Visual C# 2010 Recipes"
Apress also writes "Pro C# 2010 and the .NET 4 platform"
O'Reilly also writes "Microsoft Visual C# 2010"
Jon Skeet and Scott Hanselman both write C# 4
yet Dino Esposito writes C# 4.0
this MSDN page is entitled Visual C# 2010 Samples, refers to C# 4.0, and people writing in the comments refer to both C# 4 and C# 4.0
If we are going to publish training material about C# 4, what term should we use?
Microsoft Visual C# 2010 is the C# specific part of the integrated development environment Microsoft Visual Studio 2010.
C# 4.0 is the language.
Microsoft .NET Framework 4.0 is the framework.
It is common to shorten 4.0 to 4.
This is a response to Adrian Grigores comment "The .NET version does determine the syntax and semantics of the C# language".
There are (at least) three partially independent version numbers - the .NET Framework version, the Common Language Runtime (CLR) version, and the C# version (see this StackOverflow question for a quite comprehensive list of Framework and CLR versions).
The C# version determines what language features are available. Language features are based on .NET Framework features - the included framework assemblies and CLR version. Finally every .NET Framework versions includes a specific CLR version that basically determines what is valid Common Intermediate Language (CIL) code and how it must be interpreted. Some examples.
C# 3.0 introduces automatic properties. This feature is build into the compiler and does not rely on new functionalities in the .NET Framework assemblies or even the Common Language Runtime (the .NET Framework 3.0 still contains the CLR 2.0). Therefore it is possible to build an application using automatic properties and targeting the .NET Framework 2.0 (maybe even 1.0 and 1.1).
C# 3.0 introduces LINQ. This feature is mainly build into the compiler but partly relies on assemblies new in the .NET Framework 3.0. LINQ to Objects for example relies on the new System.Core.dll containing the Enumerable class. It is however possible to fake this dependencies and therefore use LINQ to Objects with the .NET Framework 2.0.
C# 2.0 introduces generics. This feature relies on extension of the CIL in the CLR 2.0. Therefore it is not possible to use generics with the .NET Framework 1.0 and 1.1.
I'd go with C# 4.0
The first and third book you quoted refers to the visual studio subproduct (Visual C#), That's why they are using 2010 as the "version" number.
So since you you are going to write an article about C#, not Visual Studio, It's either 4 or 4.0. And since '4.0' makes it clearer that you are talking about a version number, C# 4.0 seems like the best choice to me.
The official name of the language is Visual C# <version>
I'll look for a reference .
Edit:
The ECMA-334 standard consistently calls it C#. So that is the name of the language.
Microsoft calls their implementation Visual C#. The other implementations (that I know of) are Mono C# and Rotor C#
And while the IDE is called Visual Studio <versionyear>, I think C# 2010 is a definite misnomer. But that doesn't lower its marketing value.
While the real technical name is C# 4.0 for the latest C# version, 2010 is the IDE's version.
For marketing purposes, 2010 might be used instead of 4.0, because people new to the language might be more tempted to the year number for it indicates that the book is tackling the technology with its recent update.
I'd say the language is C# 4.0, the tool is Visual C# 2010 (like Visual C# 2010 Express).
I would opt for C#4.0.
In the past you had
.NET 1.0 (C# 1.0)
.NET 1.1 (C# 1.0)
.NET 2.0 (C# 2.0)
.NET 3.0 (C# 2.0)
.NET 3.5 (C# 3.0)
and now
.NET 4.0 (C# 4.0)
The language is C# 4.0. The product is Visual C# 2010.
C:\Users\pminaev>csc /?
Microsoft (R) Visual C# 2010 Compiler version 4.0.30319.1
and then opening "%ProgramFiles%\Microsoft Visual Studio 10.0\VC#\Specifications\1033\CSharp Language Specification.doc", on the very first page
C# Language Specification
Version 4.0
IMHO i would call it by it's version.. so C# 4.0. Previous Versions were called by the same like C# 3.0 etc.
regards
Since C# 4.0 came out and currently can only be developed in Visual Studio 2010 (and no other version of VS), people seem to use both terms interchangeably.
Personally, I would rather see C# 4.0, as that is the version of the language, not of the IDE.
Using C# 4.0 may be the official name, but especially if your book is targeted to those 'less in the know', than adding 2010 and whatnot may let people know which version of Visual Studio you are talking about. If it's for professionals, you'll have no problem throwing around C# 4, but for beginners, saying C# 2010 will tell them the IDE they need to use. It's clearer, though not official.

Does MEF require .NET 4?

I am using Visual Studio 2010, try to create a MEF application. Does this require .NET 4.0 or can I target .NET 2.0?
Yes you do:
Application requirements change
frequently and software is constantly
evolving. As a result, such
applications often become monolithic
making it difficult to add new
functionality. The Managed
Extensibility Framework (MEF) is a new
library in .NET Framework 4.0 that
addresses this problem by simplifying
the design of extensible applications
and components.
From:
http://mef.codeplex.com/
Edit:
The question about targeting .net 2.0 is answered here:
http://mef.codeplex.com/Thread/View.aspx?ThreadId=54008
MEF is not supported on .NET 2.0 as it
depends on LINQ and Expression trees.
Currently we do not have a .NET 2.0
version of MEF planned.
Strictly speaking you don't have to have .Net 4.0 installed. You can use MEF with .Net 3.5 - if you reference System.ComponentModel.Composition.dll.
As DannyLane says, however, you do need the LINQ functionality so you can't target .Net 2.0.

Which C# version can we upgrade to while retaining runtime compatibility with C# 2.0?

We have a module for EpiServer which is written in C# 2.0 which we are continuing to develop. If the only thing we know about our customers is that our current module works fine, which version of C# may we upgrade to which will still work with the customers' current runtime?
All versions of the C# compiler after 2.0 can be used to target the 2.0 CLR / Runtime. This is called down targeting. The compiler will only let you use features supported on the previous version of the runtime and will provide errors if you attempt to use features that are not. For example using dynamic when targeting 2.0.
The CLR version hasn't changed since 2005, it is still the 2.0 version. That's about to change, 4.0 will be released in the spring.
Your only other consideration is what .NET assemblies you take a dependency on. Stuff like WPF, WCF and Linq isn't likely to be available if your customer got stuck at the .NET 2.0 release. You can easily avoid creating such a dependency in VS2008. Project + Properties, Application tab, Target Framework combo.
3 and 3.5 shuold work fine!
C# isn't the runtime; it is the language. You need to be very clear about which you mean.
Targetting .NET 2.0:
You can use VS2008 and C# 3.0 to target .NET 2.0, including using all the C# 3.0 language features such as LINQ via things like LINQBridge. You should not, however, that you might accidentally take a reference to .NET 2.0 SP1 runtime features (TimeZoneInfo ?), or bugs/ "features", so you should test on the actual target framework.
Targetting C# 2.0:
If you want language compatibility, you can set this in the project (disabling C# 3.0 features), but again this isn't 100% - it will miss some things like type-inferencing enhancements; the following is fine in C# 3.0 but not C# 2.0, yet compiles with ISO-2 enabled:
int[] arr = {1,2,3};
string[] arr2 = Array.ConvertAll(arr, delegate (int i) {return i.ToString();});

Categories

Resources