I'm pretty familiar with C++, so I considered learning .NET and all its derivatives (especially C#).
Along the way I bumped into C++/CLI, and I want to know if there is any specific use for that language? Is it just suppose to be a intermediate language for transforming from native C++ to C#?
Another question that popped to my head is why are there still so many programming languages in .NET framework? (VB, C++/CLI, C#...)
Yes, C++/CLI has a very specific target usage, the language (and its compiler, most of all) makes it very easy to write code that needs to interop with unmanaged code. It has built-in support for marshaling between managed and unmanaged types. It used to be called IJW (It Just Works), nowadays called C++ Interop. Other languages need to use the P/Invoke marshaller which can be inefficient and has limited capabilities compared to what C++/CLI can do.
If you need to interop with native C++, classes that have instance functions and need the new and delete keywords to create/destroy an instance of the class then you have no choice but use C++/CLI. Pinvoke cannot do that, only the C++ compiler knows how much memory to allocate and how to correctly thunk the this pointer for an instance function.
The .NET framework contains code that was written in C++/CLI, notably in System.Data and WPF's PresentationCore. If you don't have unmanaged interop needs or don't have to work with a legacy code base then there are few reasons to select C++/CLI. C# or VB.NET are the better choices. C++/CLI's feature set got frozen around 2005, it has no support for more recent additions like lambdas or Linq syntax. Nor does the IDE support many of the bells and whistles available in the C# and VB.NET IDEs. Notable is that VS2010 will initially ship without IntelliSense support for C++/CLI. A bit of a kiss-of-death there.
UPDATE: revived in VS2012, IntelliSense support is back. Not in the least thanks to C++/CX, a language extension that simplifies writing WinRT apps in C++. Its syntax is very similar to C++/CLI. The Windows Forms project templates were removed, the designer however still works. The new debugging engine in VS2012 doesn't support C++/CLI, you have to turn on the "Managed Compatibility Mode" option in Tools + Options, Debugging, General.
First C# is not a 'derivitive' of .NET. .NET is not a language, it is an application framework and class library based on the CLR, for which a number of languages exist.
That said, the most compelling reason to use .NET is that it is a well designed class library and a much easier way to develop for Windows than Win32 or MFC. However I personally decided that I'd rather learn a new language altogether than learn extensions to an old one, and because C# was designed from the ground up to work with .NET, I suggest that is the language of choice for .NET.
C++/CLI is useful is you want to use .NET with some legacy code, and I have used it for creating Windows Forms GUIs and gluing them to existing application code. Its other raison d'etre is that it is the only .NET language that supports mixed managed and native code in a single load module, so it is good for both performance and reuse of legacy code.
With respect to the number of languages, Microsoft want every Windows application to be based on .NET because it is better for the security and stability of their OS. The only way that will happen is by supporting multiple languages. Think of .NET as an application platform or OS API, and then the question makes less sense; there will be many languages for .NET for the same reason as there are many languages for any platform. Those reasons are many, including commercial advantage, application fit, politics, supporting existing developers, choice and no doubt more.
Microsoft has changed its stance on this a few times. It was originally intended as a full-fledged language, essentially something that they wanted all native developers to move to, abandoning native C++ as much as possible.
Then a few years ago, they realized that this simply wasn't what their customers wanted. Developers who are moving to .NET anyway generally jump to a language like C#, and the rest have reasons to keep their code in the native world, so they stay with C++.
So now, Microsoft intends for C++/CLI to be a "bridge" between native C++ code and managed code written in some .NET language. It's no longer a language they recommend you switching your entire codebase to.
It's indeed mainly intended as intermediate language to easily link .net code with native, unmanaged C++. Do yourself a favour, don't use it if you don't need to. C++/CLI syntax is a mess.
Regarding your second question ... I think today C# is the dominant language in .net, but not everyone likes its style and paradigms. .net's architecture makes adding new languages easy (see F#, which aims at functional programming).
I've used C++/CLI to create .NET API's for some unmanaged C++ libraries. Passing and marshalling of parameters takes some getting used to (depending on used types), but once you've got the hang of it, it's really a nice way to bridge the gap between the managed and unmanaged world.
I have not looked at C++/CLI but it harnesses the .NET world - think of it as a in-between C++ and C# where you have the best of both worlds. It could be useful in situations where you want to use C++ that can easily access .NET objects and it's core BCL. Have a look here at this article discussing the primers of C++/CLI. Unfortunately, I have not heard of a Managed C++ application as it has ruffled a lot of C++ friends on the syntax side of things and lost gathering of followers who went back to the unmanaged world of C++.
Hope this helps,
Best regards,
Tom.
for me, i have to use it when there is no other way to reuse c++ class
This post is old but the most important message in my oppinion is missing: You use it for being able to see and manipulate the source code of C++ frameworks you use in C#. Examples: You don't use compiled OpenCV binaries, instead you got the OpenCV sourcecode in your solution and can add simple some Extensions, or deep check how some behavior exists. Or in finanicial math you could QuantLib Sources, and so on. This is much better than having already compield libraries that act as black boxes in a lot of ways. C++/Cli in .NET solves this.
Just so you know. Unless you specify the code to be compiled as unmanaged, when compiling with CLR support it will be compiled as managed code.
While CLI C++ is nice. I find it a pain to code in. There is just something about it that makes me not want to program in it. It isn't even the "^". It is like using a broken .net. I spent 40 minutes coding something fully managed in it that took me 10 minutes in C#. I mean, sometimes I just give up and use C# because it frustrates me when coding in it. I mean if you are going to use .net you might as well use C#(over CLI C++).
Related
Or I should ask how helpful and benifitial will it be to start with C++
This may seem irelevant but it has some significance for me,may be few others like me.
I just want to know ,How Important is it to Learn C++ , COM and ATL while you are a .NET programmer?
I love programming with .NET and C# .Visual Studio just has it's own charm of intellisence ,Color Coding and other pretty features , which make us addicted to it.
I was thinking , almost we can build anything with C# and still it holds true mostly, but it lags sometimes like:
While I try to create a Shell Extension , then it is highly suggested to use unmanaged code instead of any managed code.
Also there are few other things like COM , ATL , which are preferred to be coded in C++ rather than C#.
I am just 4 years in IT industry and love to be Solution Architect.
So need all your inputs to know , how important/helpful will it be in my future venture if I am doing my Current COM Project with C++ , which integrate with .NET UI.
Is there any implementation of C++ and .NET in common domains like Health Care, Banking and Telecommunication.
The issue (at least for the specific cases you mention, such as shell extensions) with trying to "integrate with a .NET UI" is that you really can't. The reason it's not a good idea to write shell extensions in managed code is that a given process can only load one version of the CLR at any given time. If two shell extensions depend on different versions of the CLR, and they both try to load at the same time, it will fail. You can't load the CLR in any way shape or form in the context of your shell extension and be a well behaved shell extension.
My advice would be to not bother with C++ until you really have a reason to learn it (despite that C++ is my favorite language). But when you do learn C++, leave your .NET baggage at the door. There are lots of things (such as excessive use of casting, constantly using new, etc) which are idiomatic C#, and are just plain wrong in C++. You will be a lot happier if you don't try to understand C++ concepts in terms of the CLR -- simply because C++ doesn't run there. You can use some of the design patterns you may have learned for C#, but how the underlying language and machine operates are completely different between the two languages.
Probably the most confusing difference for new C or C++ programmers is the concept of undefined behavior. The C and C++ standards are written in such a mannar as to not be tied to a particular machine. This is in stark contrast to architectures like Java or .NET, where the language is actually defined in terms of a virtual machine (and therefore is extremely dependent on that VM). This leads to places where the standard literally does not say what the correct output of a program should be; and instead says "however the underlying machine usually does this". You'll probably notice this quite a bit if you're ever dealing with floating point math. While C# has strict and specific rules about how and where floating points are calculated and rounded, C and C++ make no such qualifications.
Once you understand C++, then you can move on to COM and ATL. COM is essentially designed to make a C++ like class structure accessible in a language (the COM ABI), machine (marshalling between 32 bit and 64 processes on the same system, etc), and location (DCOM provides RPC facilities) independent way. If you don't understand the C++ object model, then you're going to have an extremely difficult time with the COM object model, because the two are extremely similar. ATL is a set of C++ class templates around COM fundamentals which simply handle some of the boilerplate for you.
I just want to know ,How Important is
it to Learn C++ , COM and ATL while
you are a .NET programmer?
Depends what you do. You are way better of learnin about databases. Pretty much every serious app uses a database.
But C++ IS ued together with .NET - especially C++/CLI (the managed variant) as it is very good for integrating C++ code with managed code effficiently. Quite often pretty much the only efficient way. Which is important if you for example raise events for market data. With a frequency in excess of 100.000 times. Per second.
But this is a NICHE. I work in the financial area, and tthe C++ uses AND integration uses are SMALL compared to the people working in .NET / In the application.
WPF applications are, at its core, managed applications? Right? So, I have to choose between using managed C++ or managed C#. I experimented with managed C++ years ago. It seemed to be not quite be ready for primetime. I'm guessing Microsoft has put more effort into managed C# than managed C++. So, it seems like using managed C# is the best alternative between the two. Is this the case? What experiences have you had with WPF in either language? Thanks in advance.
Managed C++ has been replaced by C++/CLI, and "managed C#" is just C#.
I would strongly recommend you to use C# for a new project, and use C++/CLI only when needed. C# has a better support, has a larger user base, and is easier to work with inside Visual Studio 2010.
Additionally, keep in mind that C++ and C++/CLI are two different languages. For my first .Net project, I chose C++/CLI because I already knew C++, and this was a very bad idea: the learning curve from C++ to C++/CLI is similar to learning C# from C++: don't fall into that trap.
C++/CLI was only really made to support writing interop layers between unmanaged code (i.e. native C/C++) and managed code. For "heavy lifting", you should definitely use C# (or VisualBasic.NET).
You can use managed C++ for your backend but, on inspection, VS (I'm using 2010 Ultimate) doesn't have any in-built templates for a C++ WPF application - only C# or VB.
I'm sure you could force it to work if you wanted to, but I'd suggest you use C#.
C# is the most used, so if you have trouble, there is more online support for C#. C# also has better support by Microsoft. It's overall just a more finished product, even now. If you really don't care yourself, i'd go with C#.
In terms of the backend, they both run on the CLR and both capable of the job. Really it just comes down to what you're most comfortable with. If you're not sure, experiment with both.
Use whatever feels most productive.
Edit:
As has just been pointed out to me though, it seems support for WPF templates (and possibly even intellisense) just isn't there for C++. So in that case I guess I'd have to recommend C#.
IMO without a doubt C# (or VB/F#).
C++/CLI is great when crossing the border of managed world and a c++ library. Complexity is higher though as subtle issues arises from the fact that one combine a managed language and an unmanaged.
Compile times are longer though as well in C++/CLI especially since the code templates are modelled after how the C# compiler works not on how the C++ compiler works.
I heard somewhere that Microsoft will be focusing their efforts on C# rather than C++ for the .NET platform. I can see signs of this being true because of the GUI designer that was available for C# but not C++.
So I would like to know if C++ in .NET is dying and if it will continue to be second to C# in the future.
If you are targeting the .NET framework in application development then yes C++/CLI is a second class citizen compared to C#. C# was specifically designed as the language for .NET framework meanwhile C++/CLI extension is there to allow developers to bridge native and managed code.
However do not confuse C++ with C++/CLI (C++ .NET is the same thing...). C++ is alive and well in areas such as the kernel, games, high-performance and server apps (e.g. SQL server) all of which are unlikely to change. On the other hand most .NET 'GUI stuff' won't use C++.
Managed C++ never really got to be what MS thought it would be. C# could do (nearly) the same thing, with a lot more intuitive and user-friendly syntax.
Apart from that, C++/CLI will not be left unsupported for a long time, as it's the easy way to create interop between .NET assemblies and native C++ assemblies. That's about all it's used for though (I'm sure there's a 0.001% of C++/CLI developers out there who disagree :P ).
C++/CLI is just the way Microsoft attracts native C++ developers to .NET. It was like a intermediate layer between native C++ and C#, but I'm pretty sure that developers prefer to choose either native C++ or C#.
Microsoft will not let C++/CLI die, at least in near future, however, without community support, C++/CLI will not be able to grow.
In this generation, not growing means close to dead.
I'm afraid it is.
The reason for this is not C# (which doesn't bring anything special and although it's a new language it doesn't lead in new language features but merely copies features of others - generics).
It's mainly because the first attempt of MS to enable C++ for .NET platform - Managed C++ - was a disaster.
After this they hired Herb Sutter, C++ guru, which made fantastic job designing Managed C++ replacement callled C++/CLI.
Why and how much C++/CLI design is superior to Managed C++ design you can find out by reading A Design Rationale for C++/CLI written by Herb.
By the way, Herb made vc compiler one of the best standard-conforming compilers for Windows after years of it being the worst one in regard to standard conformance.
No. It was born dead. It always has been treated as a second class citezen with no vitality roadmap.
i think YES , its dying , actually it already died ;) , coz there arent lots of people who use it , they use whether c++ or c#.
see this
I don't think it's necessarily going away, but the reason for using it almost always comes down to whether or not you need the performance benefits that come with it. If C# can do the same thing at 90% of the efficiency of C++, isn't that really good enough?
What can be done in VC++ (native) that can't be done with VC#?
From what I can tell the only thing worth using VC++ native for is when you need to manage memory yourself instead of the CLR garbage collector, which I haven't seen a purpose in doing either (but thats for another question to be asked later).
Cross-platform development. Yes Mono exists, and Java's somewhat more predictable to have it function EXACTLY the same on more platforms, you can find a C/C++ compiler for just about any platform out there, where you can't with C#.
Also linking into 3rd-party libraries, while I'm sure there's a way to leverage them in C#, you'll be able to take advantage of them without interop (Marshaling, etc) in C++.
Edit: one last thing: RELIABLE memory management. Yes you can use dispose(), and try-finally, but there's nothing quite like KNOWING the memory is gone when it's popped off of the stack. Through techniques like RAII, when you use well-constructed classes, you will KNOW when your classes release resources, and not waiting around for the GC to happen.
With P/Invoke there is very little that is impossible in .NET (most obviously device drivers).
There are also things where the advice is to not use .NET (e.g. shell extensions, which get loaded into any process that opens a file dialogue1).
Finally there are things which will be much harder in .NET, if possible at all (e.g. creating a COM component that aggregates the FTM).
1 This can create a problem if that process is already using a different version of .NET. This should be alleviated in the future with .NET 4 having the ability to support side by side instances of the runtime.
I'm not sure if you're talking about language features or applications. My answer though is for applications / components.
Really there are only 2 things you cannot do in C# that you can do in C++.
You cannot use C#, or any other .Net language, to write a component for a system that only accepts native components
You cannot use C#, or any other .Net language, to alter certain properties of a CCW for which the CLR does not allow customization
The most notable item here is Device Drivers. This is a framework that only accepts native components and there is no way to plug in a managed component.
For everything else it's possible to do the same thing in C# as it is in C++. There are just a lot of cases where you simply don't want to and a native solution is better. It's possible for instance to manage and manipulate memory in C# via unsafe code or IntPtr. It's just not nearly as easy and generally there's no reason.
You can't write device drivers for one.
I think there are several important points:
You can do anything in C#/C++/Java/Python/Lisp or almost any other language, finally all of them Turing complete ;)... The question is it suits your needs?
There is one big and extreamly important limitation of C#... It runs only one single platform Windows... (Mono is still not mature enough).
There are many applications where GC is just a waste of resources, applications that can't afford you throw up 1/2 of memory untill next gc cycle: Games, Data Bases, Video auido Processing and many other mission critical applications.
Real Time applications (again games, video processing and so on). Non-deterministic GC makes life much harder for them.
In fact, most of desktop applications: Web Browsers, Word Processors, Desktop Environment itself (like Windows Explorer, KDE or Gnome) are written in compiled languages with careful thinking about resources... Otherwise, they would just be terrible bloated applications.
Whereas writing shell extensions in Windows XP was possible in C# it is next to impossible to write shell extensions for Vista and Windows 7. Shell extensions and Namespace extensions (and anything else that uses the new Properties system) (kindof) must be done in C++ unless you're into pain.
There are two obvious answers:
VC# can never run without the .NET
framework. Native C++ can. That may
be necessary in some areas (others
have mentioned device drivers, but
more common examples might simply be
clients where the .NET framework is
not installed. Perhaps you're
distributing an application and you
know not all of your customers are
willing to install .NET, so your
sales would go up if you made an app
that just worked without the
dependency on .NET. Or perhaps you're
working on some mobile device where
the couple of megabytes taken up by
the .NET CF can not be justified. Or shell extensions where using .NET can cause nasty problem for the user.
And VC# can never use C++ language
features. Native C++ can. (Managed
C++ can too, of course, but that's a
different issue). There are, believe it or not, things that can be done more conveniently or elegantly in C++. And they're only accessible if you're programming in C++.
System calls are no problem, however. p/invoke lets you do those from C#, almost as easily as you could from C++.
inline assembler
You cannot use C++-Libraries with classes (P/Invoke can only be used for functions AFAIK)
You cannot use callbacks with P/Invoke.
Is C# in particular and .NET in general self compiling yet (this is not a troll, I genuinely don't know)? If not, you can use VC++ to write C# and .NET, but you can't use C# to do the same job.
This is tongue in cheek, but it also is an answer to your question... you can screw things up much more severely in VC++ than you can in VC#. Not that you can't manage to screw things up severely in VC#, but in general, you can screw them up easier and more thoroughly in VC++.
Again, kind of tongue in cheek, but also an answer to your question. Perhaps not what you were hoping for, but... :-)
There's also hard real-time applications. Any language with a GC cannot be used, just in case it decides to collect during a time-constrained part of the code. Java was notorious for not even allowing you to try (hence the EULA about not using it for software "intended for use in the design, construction, operation or maintenance of any nuclear facility"
(yes, I know they've since made a modified version of Java for real time systems).
For example, it makes sense to use C++ if it's harder to translate the header files for existing libraries than it is to give up the existing managed libraries.
The Main difference is:
C++ is a core language with which you can build stand-alone programs. These Programs communicate directly with the the operating system and nothing else. C++ compilers exist for more or less all platforms (operating systems).
C# is a language that conforms to the CLS. A program written in C# can not start without a CLI engine (.NET Framework, Mono, etc.). A Program written in C# communicates with the .NET framework AND with the operating system. You have a man in the middle. Like all servicing personal, this man can help but it will cause additional trouble. If you want to port, you have a different man in the middle etc. CLI Implementations do not exist for all platforms.
By my opinion every additional framework is a additional source of problems.
Using SSE instructions seems to be one of these cases. Some .NET runtimes will use some SSE instructions, depending on your code. But in VC++, you can use the SSE intrinsics directly. So, if you're writing a multimedia code, you'd probably want C++. (C++/CLI might work as well, presumably)
I'm not seeing any real advantages, other than the fact that you have a C++ syntax, and with it, things like pointers and destructors.
If you're talking about why you would use C++/CLI over C#, I think the main reasons are that:
it might be more natural for C++ developers (though I think this is probably not true)
C++/CLI has very nice capabilities for bridging the native and managed environments (using the 'IJW' - It Just Works - technology)
I think that Herb Sutter probably gives the best overview:
A Design Rationale for C++/CLI
If you want to know why you might want to use native C++ over C#/.NET, this boils down to why you would want a managed environment (safety, easier development) over native code (absolute control, possibly speed advantages). There are arguments for each, and the answer really depends on what you want to develop and what your market might be.
I think you're referring to C++/CLI and comparing it to C#. C++/CLI isn't a 'flavor' of C++. It's an entirely new language with entirely different standard libraries and entirely different conventions.
At work we find that C++/CLI is valuable as a glue language between C++ and .NET, but we don't use it for anything besides interface glue - C# has enormous advantages over C++ in all other applications.
If you're referring to MS C++ extensions like what Adam describes, there's no reason not to use them if they make your job easier.
the really good reason to use C++\CLI is to communicate DotNet language with Native C++, for example many companies migrate first their GUI to .Net and let some logic in C++, and C++\CLI is the good bridge to communicate beteween two techno, you can also use COM components for that, but for many reasons it's not the good choice.
I don't think comparing different flavors of C++ to each other is the same question as comparing C++ to C#. C# is a very different beast compared to the differences between different flavors of C++.