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I'm looking at Script#, JSIL and SharpKit as a tool to use to compile C# to Javascript, so I can program the client side functions of AJAX using C# in Visual Studio.
What are the pros and cons of each JSIL, Script# and SharpKit?
My project is a MVC4 project using razor engine and C#, if it matters.
If you're looking to integrate directly with an MVC project, something like Script# or SharpKit or something is probably your best bet - I know for a fact that Script# has stuff built in to make that sort of integration easier, so I would start there.
If you do want to try using JSIL, it probably has the core features you need, but things that you might want - like visual studio integration, automated deployment, etc - are not there. At present it is primarily targeted at cross-compilation of applications, so it does a good job of that but not as good a job of other use cases.
I'll try to give a summary of reasons why you might want to consider JSIL over those other alternatives - I can't really comment on the pros and cons of those alternatives in depth since I haven't used them:
JSIL has extremely wide support for the features available in C# 4. Notable ones (either because other tools don't support them, or they're complicated) include:
dynamic, yield, Structs, ref / out, Delegates, Generics, Nullables, Interfaces, and Enums.
Some of the above, of course, don't have complete support - to get an idea of things that absolutely will work, you can look at the test cases - each one is a small self-contained .cs file that is tested to ensure that JSIL and native C# produce the same output.
The reason for this extensive support is that my goal is for JSIL to enable you to translate a completely unmodified C# application to working JS. For all the demos up on the JSIL site, this is true, and I have a few nearly finished ports of larger real games in the wings for which this is also true.
Another reason is that JSIL makes it relatively straightforward for your C# and your JavaScript to talk.
All your C# types and methods are exposed via an interface that is as javascript-friendly as possible. The JS versions have basic overload resolution and dispatch so that native C# interfaces are callable from script code as if they were native JS in most cases. You don't have to take any steps to specifically tag methods you wish to expose to JS, or give them special names, or anything like that unless you want to.
When you want to call out from C# to JS, you can do it a few ways:
JSIL.Verbatim.Expression lets you insert raw javascript directly into the translated version of a function.
JSIL.Builtins.Global can be combined with dynamic and var to write JavaScript-like code directly in your C# function bodies.
The JSReplacement attribute can be used to replace invocations of a C# function with a parameterized JavaScript expression.
All of the above features can be combined with JSIL's mechanism for altering type information, called Proxies, to allow you to alter the type information of libraries you use, even if you don't have source code, in order to map their methods to JavaScript you've written.
And finally, C# methods that aren't translated to JS produce an empty method called an External that you can then replace with JavaScript at runtime to make it work again. Any External methods that you haven't replaced produce clear warning message at runtimes so you know what's missing.
JSIL makes aggressive use of type information, along with metadata you provide, to try and safely optimize the JavaScript it generates for you. In some cases this can produce better equivalent JavaScript than you would have written by hand - the main area where this is true at present is code that uses structs, but it also can apply in other cases.
For example, in this code snippet, JSIL is able to statically determine that despite the number of struct copies implied by the code, none of the copies are actually necessary for the code to behave correctly. The resulting JavaScript ends up not having any unnecessary copies, so it runs much faster than what you'd get if you naively translated the semantics of the original C#. This is a nice middle ground between writing the naive struct-based thing (Vector2s everywhere!) and going completely nuts with named return value optimization by hand, which, as I've described in the past, is pretty error-prone.
Okay, now for some downsides. Don't consider this list exhaustive:
Large portions of the .NET BCL don't have implementations provided for you by JSIL. In the future this may be addressed by translating the entire Mono mscorlib to JavaScript, but I don't have that working well enough to advocate it as an immediate solution. (This is fine for games so far, since they don't use much of the BCL.) This issue is primarily due to the IP problems related to translating Microsoft's mscorlib - if I could do that legally, I'd be doing it right now - it worked the last time I tested it.
As mentioned above, no visual studio integration. JSIL is pretty easy to use - you can feed it a .sln file to get a bunch of .js outputs automatically, and configure it automatically with a configuration file next to the project - but it's nowhere near as polished or integrated as say, Script#.
No vendor or support staff. If you want a bug fixed yesterday or you're having issues, I'm pretty much your only bet at present (though there are a few prolific contributors helping make things better, and more are always welcome!)
JavaScript performance is a goddamn labyrinth full of invisible land mines. If you just want apps to work, you probably won't have any issues here, but if like me you're trying to make real games run fast in browsers, JavaScript will make your life hell and in some cases JSIL will make it worse. The only good thing I can say here is that I'm working on it. :)
JavaScript minifiers and optimizers like Closure are explicitly not supported, because they require your code generator to jump through a bunch of hoops. I could see this being a real blocker depending on how you intend to use your code.
The static analyzer is still kind of fragile and there are still gaps in the language support. Each big application I port using JSIL usually reveals one or two bugs in JSIL - not huge game breakers, but ones that definitely break a feature or make things run slow.
Hope this information is helpful! Thanks for your interest.
Script# pros:
Free
Open source
Generates clean JavaScript
Script# cons:
Supports a subset of C# 2.0 language only
Can be compiled only in a separate project, cannot mix / re-use code between client and server
Low frequency of version updates
Does not offer support
Limited 3rd party library support, C# API is different than JavaScript API.
Not open source
Debugging in JavaScript only
SharpKit pros:
Commercial product
Supports full C# 4.0 language
High frequency of version updates
Support is available
Client / server code can be mixed and re-used within the same project
Extensive 3rd party library support, maintained as open-source - C# API matches exactly to JavaScript API
Supports basic C# debugging for Chrome browsers
Generates clean JavaScript
SharpKit cons:
Has a free version with no time limit, but limited to small / open-source projects
Not open source (only libraries are open-source)
JSIL pros:
Free
Open-source
JSIL cons:
Converts from IL (intermediate language), not from C#, which means a lower abstraction layer since code is already low-level.
Complex generated JavaScript code - almost like IL, hard to read and debug
Answers to feedbacks:
Kevin: JSIL output is not bad, it's simply generated to achieve full .NET behavior, much like SharpKit's CLR mode. On the other hand, SharpKit supports native code generation, in which any native JavaScript code can be generated from C#, exactly as it would have written by hand.
Sample of SharpKit's clean generated JavaScript code:
http://sharpkit.net/Wiki/Using_SharpKit.wiki
Developer can choose to create more complex code generation and gain more features, like support for compile-time method overloads. When specified, SharpKit generates method suffixes to overloaded methods.
Script# requires .NET 4 in order to run, but it does not support full C# 4.0 syntax, like Generics, ref and out parameters, namespace aliases, etc...
Another alternative is WootzJs. Full Disclosure, I am its author.
WootzJs is open-source and strives to be a fairly lightweight cross-compiler that allows for all the major C# language features.
Notable Language Features Supported:
yield statements (generated as an efficient state machine)
async/await methods (generated as a state machine like the C# compiler)
ref and out parameters
expression trees
lambdas and delegates (with proper capturing of this)
generics support in both the compiler and the runtime (invalidly casting to T will throw a cast exception)
C# semantics (as opposed to Javascript semantics) for closed varaibles
It is implemented using Roslyn, which means it will be first in line to take
advantage of future language improvements, since those will now be implemented via Roslyn itself. It provides a custom version of mscorlib so you know exactly what library functionality is actually available to you in your scripts.
What Are its Downsides?
The Javascript is not intended to look "pretty". It is clearly machine generated, though individual methods should be easy to reason about by looking at them.
Because of its extensive support for core libraries and reflection, the generated output is not the smallest on the block. Minification should produce an ~100k JS file, but minification is not yet supported.
WootzJs unabashedly pollutes native types with functions to encapsulate behavior for those types that would only be found in C#. For example, all the methods of System.String are added to the native Javascript String type.
Little support for binding to 3rd-party Javascript libraries presently exist. (Currently only jQuery)
Comparisons with Other Cross-Compilers:
Script# is very stable and has extensive integration with 3rd party Javascript libraries. Furthermore, it has excellent Visual Studio integration, and it provides a custom implementation of mscorlib. This means that you know precisely what functionality has actually been implemented at the tooling level. If, for example, Console.Write() is not implemented, that method will not be available in your editor.
However, due to its custom parser, it is still stuck in C# 2.0 (without even the generics found in that version of C#). This means that the modern C# developer is giving up an enormous set of language features that most of us depend on without reservation -- particularly the aforementioned generics in addition to lambdas and LINQ. This makes Script# essentially a non-starter for many developers.
JSIL is an extremely impressive work that cross-compiles IL into Javascript. It is so robust it can easily handle the cross-compilation of large 3d video games. The downside is that because of its completeness the resultant Javascript files are enormous. If you just want mscorlib.dll and System.dll, it's about a 50MB download. Furthermore, this project is really not designed to be used in the context of a web application, and the amount of effort required to get started is a bit daunting.
This toolkit too implements a custom mscorlib, again allowing you to know what capabilities are available to you. However, it has poor Visual Studio integration, forcing you to create all the custom build steps necessary to invoke the compiler and copy the output to the desired location.
SharpKit: this commercial product strives to provide support for most of the C# 4.0 language features. It generally
succeeds and there's a decent chance this product will meet your needs. It is lightweight (small .JS files), supports modern C# language features (generics, LINQ, etc.) and is usually reliable. It also has a large number of bindings for 3rd party Javascript librarires. However, there are a surprising number of edge cases that you will invariably encounter that are not supported.
For example, the type system is shallow and does not support representing generics or arrays (i.e. typeof(Foo[]) == typeof(Bar[]), typeof(List<string>) == typeof(List<int>)). The support for reflection is limited, with various member types incapable of supporting attributes. Expression tree support is non-existent, and the yield implementation is inefficient (no state machine). Also, a custom mscorlib is not available, and script C# files and normal C# files are intermingled in your projects, forcing you to decorate each and every script file with a [JsType] attribute to distinguish them from normally compiled classes.
We have SharpKit for two years and I must say that's upgraded the way we write code.
The pros as I see them:
The code is much more structured - we can now developed infrastrcture just like we did in C# without "banging our heads" with prototype.
It is very easy to refactor
We can use Code Snippets which results in better productivity and less development time
You can control the way the JS is rendered (you have several modes to choose from).
We can debug our C# code in the browser (Currently supported on Chrome only, but still :->)
Great support! If you send them a query you get a response very fast.
Support a large number of libraries & easily extensible
The cons:
The documentation is a bit poor, however once you get a hang of it you'll boost your development.
Glad if this could help!
For ScriptSharp, this stackoverflow link could be of help.
What advantages can ScriptSharp bring to my tool kit?
If you have any SVN tool, please download a sample from https://github.com/kevingadd/JSIL, this is a working source code and can help you go miles.
target state: Porting VB6 Code into C#, undertake the whole project with all conceivable processes that are involved.
What would be your approach if you do not have knowledge about the domain?
There is nearly any documentation, just legacy code (up to 100.000 - 300.000 lines of code and comments vb6 files that contain up to 14.000 lines of code) written in VB6.
Disclaimer: I work for Great Migrations
We rewrite large VB6/ASP/COM applications to .NET (primarily C#) for a living and we have developed a software analysis and reengineering tool to help us do it. This tool is essentially like a VB6/ASP/COM compiler and a decompiler that authors .NET codes. Of course since the VB6 platform is very different from .NET, a direct compile/decompile is not desirable or viable, so our tool has an "analyzer" that implements various code reengineering algorithms to deal with VB6-C# incompatibilities. There is also a programmable "author" that allows the migration team to prescribe rules for setting up .NET code files, restructuring the code, and doing things like replacing COM APIs and ActiveX controls with .NET classes -- depending on what the team needs or wants.
As a by product of compiling and analyzing the code our tool produces a model of the entire VB6/ASP/COM system being upgraded. This model can be used to produce extremely detailed reports about the internal structure of the system. These models can be used to help reverse-engineer the code -- if you know the right questions to ask and you would need to understand the problem domain to do a good job.
Of course once you have build-complete .NET, you can use the various analytics and code review tools that work off assemblies. Some versions of Visual Studio have these tools and there are open source tools such as FxCop, NDepends). There are also some fantastic dynamic analysis tools (EQUATEC Tracer) that I have used.
In the end though migration teams are going to very hard pressed to verify any unknown system. Even if you are staying on the same platform, you would unable to prove an application it is "correct" if you do not know how to run it and how to setup/enter expected inputs and find/verify expected outputs. We normally leave this to the customer!
If we are doing verification for the customer, we rely heavily on side-by-side testing to validate the new version of your system -- assuming we know how to run the legacy application we assume that given the same sets of inputs and usecases it should exhibit the same behaviors and produce the same results. I have heard this Approval Tests in unit testing circles.
I admit we also rely heavily on the knowledge that the VB6/COM code is a complete, detailed, formal and production tested description of the data structures and logic of the system and that we are putting this information through a tested and retested systematic transformation. We have been developing compilers since 1977 and we have worked very hard on this VB6/ASP compiler to make sure the .NET codes that we generate preserves the semantics of the original VB6. It is not 100% every time - but it is getting closer all the time. Then again doing things by hand does not guarantee 100% correct code on the first try either...
mark's answer about Great Migrations is excellent. Do be aware there are competitor automatic tools, which also have a very good reputation.
Artinsoft's VB Upgrade Companion
Francesco Balena's VB Migration Partner
First of all, until now, all my programming education, has been targeted to console applications, just like everyone who starts learning C and C++. (the 2 languages i know)
Now, i want to jump to the nice graphical World.
So, I am exploring Windows Forms, i have already got many headaches trying to understand the language that it uses (quite diferent from native C++), but i managed to do a couple of things like using textbox and buttons.
Well, the thing is, i have read in many places that, in order to avoid headaches trying to code winforms in C++, i'd better "Build the GUI in C#, because it's way easier, and the logic, and code in C++". And that is my question, i don't understand that statement, at all.
What is that supposed to mean?
Also, it's C# THAT similar to C++, as to affirm that statement? Cause, if C# was too diferent to C++, i would have to learn the whole C# language
hope you understand my doubt.
PD : Sry about my bad english.
Joan, while it is certainly possible to develop an applications Front End in C# and the logic in C++ I believe it to be a huge waste of effort to do it this way since you only complicate yourself for no real benefit since you can code both things in the same language.
C# has many advantages over C++ and I personally use mostly C#, but I can clearly see many programmers who love C++.
Now going into your question regarding the similarities between C++ and C# the answer is yes and no. Yes in the sense that C#'s syntax is clearly derived from C++. Many things like ifs and for loops are written exactly the same, so if you know how to write an if in C++ you can write it in C#.
The difference (and a critical one that is) lies in the way the languages work. C++ is an strictly compiled language (it goes from C++ code to machine code). C# is an interpreted language (it goes from c# to MSIL and during runtime to machine code). In C# you can't use pointer arithmetic without explicitly allowing, in C++ you can (and will) use pointer arithmetic. C# has garbage collection, C++ does not.
In the end, as I said in the first paragraph you can use both languages to build an application, but it would be highly complicated. My advise to you is to learn a bit of C# and then decide which language you would prefer to build your GUI application. But don't believe even for a second that C++ can't be used to build a front-end since there are a myriad of frameworks for that. One I remember from the top of my head is Qt.
Another option for you is to use "C++/CLI" which is a flavor of C++ which can use the .NET Framework (the same framework C# uses)
EDIT: Thanks Jerry for pointing out that Managed C++ is obsolete and that C++/CLI is the one!
C# has braces, semicolons, and uses the concept of classes. It has "C derived" syntax, but otherwise is very dissimilar to C++. Java is really the precursor to C#, not C++.
You can build application GUIs using C#, and then use various methods of calling into C++ (such as P/Invoke). Unless you are using lots of existing libraries, or looking for absolute performance, its going to be a headache.
If you are looking for examples of modern Windows GUIs using C++, take a look at the Hilo example program.
It is not very difficult to switch to a new language. The few keywords you would have to learn are not the issue. What costs most energy if to get used to the new environment and class libraries. That is probably what you mean and it is true, you'll need some time.
Now coming to the split GUI in C# and code in C++, then you'll have to make all bindings and marshalling of parameters if there are buffers and strings for example. I don't think this would make your life any easier. Interfacing with native Dlls can become some pain. However if you use third party dlls and have already a large working codebase you could try to compile the logic code with /clr enabled. This generates a DLL that can be used from within .NET directly.
NOTE: WinForms is now out-of-date for new applications, consider using WPF instead. It scales nicely, but the learning curve might be steep for newcomers.
Please note that you have native C++ and C++/CLI, the first one is the one you have learned, but the second one is the one you will need to use if you want to combine it with a C# GUI. However, I would suggest you to stay away from C++/CLI because this will cause a lot of confusion if you don't have a solid ground in C++, C# and .NET.
The reason that you can't use the native C++ is because C# is a managed language, so you will either have to find another GUI that fits with C++ or you will have to go C# for everything. For more information about managed see the environment part of Difference between C++ and C#, the article will also provide you with a good comparison between both.
Well, this aint a direct answer but hope it will help you. Since you stated that, you are just started and you want C++ combined with GUI, I suggest you to take a look at Qt. IMO I found C++ and GUI made easy in Qt. Also it's good too.
Although it's not a direct response to the question you're asking, I'd first caution that WinForms are already basically a dead-end, so for new code you'd be much better off avoiding them. If you're going to do a GUI in .NET, the currently preferred choice is WPF.
Some people find C# an easier way to do a GUI. It's definitely true that Microsoft provides considerably more in the way of Wizards and such to do it with little or no coding if you use .NET for the job. Other people (especially those with more experience doing so) can produce a GUI in C++ just quickly (or even a little more so) using C++ instead.
Mixing languages like this can work well in relatively large projects where you have completely separate teams of people working on the different parts. For smaller projects where the same people typically work on both parts, the difference in syntax is at just about the worst possible level -- not enough different to really shift gears and think differently, but still enough different that you can't plan on just typing things and having any hope of them compiling. All in all, you're usually a lot better off picking one language and sticking to it.
We are an team that are dedicated C#, and will start with an new project, there the customer really wants it in VB.NET.
Are there a bad choice to do the development in C# and then convert it and deliver in VB.NET.
Are there any tools that will make this easier to us than any simple converter?
I wouldn't recommend using a converter for a whole project. They're OK for code snippets and perhaps a class at a stretch, but even with two languages like C# and VB.NET based on a common runtime there'll be things that can't be converted.
As I see it you have the following choices:
Convince the customer that writing the application in C# is for the best - it's the language you know and you'll be able to deliver a higher quality product in a shorter time.
Write it in VB.NET, but point out that it will take longer to deliver.
Don't take the project. I'm assuming that this is not an option, but I'm including it for completeness.
Each language has its unique features and specialties. It is an illusion to believe that code written in C# can seamlessly be converted to VB.net. If you do automatic conversion, you'll have to fix it manually afterwards (because it is unlikely that your project will compile) and it will have poor quality, look bad and not be optimized.
I think it is a bad idea to rely on automatic conversion if your customer wants a solution in VB.NET. The code written by an automatic converter will often use a bad coding style for that language - even if the end result is the same.
It might be OK to use an automatic conversion tool occasionally to aid the development process if you are unsure of the exact VB syntax for a C# construct. You should check the result of the conversion is a best practice in VB.NET and not just copy and paste converted code without reading it. Conversion tools can make errors or produce ugly code that a human programmer would not write. Code committed to the project should be reviewed, preferably by one of the team members with the most experience in VB.NET.
You should strive to use the best practices for VB.NET so that your customer can easily understand and maintain your code.
If you feel that your team is unable to complete the project to a high quality in VB.NET then as ChrisF mentions you might want to consider:
Declining the project.
Convincing the customer to accept a high quality C# solution instead of a low quality VB.NET solution.
Alternatively you could try to gain the competences in VB.NET you are currently missing. Some examples of ways to approach this:
Attending courses on VB.NET so you at least know the basics.
Buying and reading books about programming in VB.NET.
Employing a new team member with VB.NET experience.
Using a consultant in the initial phases to help start your project and review code until your team is able to produce high quality VB.NET code on its own.
Attempting a smaller project in VB.NET first to gain some experience.
Are there any tools?
Kind of. I don't like any of them, as they don't look "trustworthy", but you can try your luck:
http://www.developerfusion.com/tools/convert/csharp-to-vb/
http://www.carlosag.net/Tools/CodeTranslator/
http://converter.telerik.com/
Would I recommend simply translating VB to C# ?
No. Because you're forced to trust in a converter. VB really, really isn't that much of a stretch from C#. If you are doing simple things, it should be pretty easy.
Regardless of your reasoning, it is possible to do this. Use RedGate's reflector http://www.red-gate.com/products/reflector/ and Denis Bauer's disassembler http://www.denisbauer.com/NETTools/FileDisassembler.aspx. You can pick your language, and the code that comes out, while not exactly what you coded, should compile back to the same IL.
You can decompile your C# binaries with JustDecompile export it as VB.net project, load the project file in VS and build.
This, however, does not usually work out of the box as you may have to fix some minor issues like:
Anonymous Types
Indexers
reimplement "unsafe" code
As you can adjust your (existing) C# test project to test the converted project along with your original implementation.
After fixing that you have the advantage to know your VB builds and runs well, which cannot be guaranteed by any automatic converter.
At a colleague's workplace, a decision is trying to be made about whether to use both languages in the workplace or to standardize on one? There are some VB.Net developers and some C# developers.
What advantages or disadvantages would there be to using both or to using one?
Edit: To clarify this question, the question is not asking the advantages of one over the other, rather what are the advantages/disadvantage of standardizing on both languages versus standardizing on one.
For instance, one point could be that C#/VB.Net may have more third party tools available and hence it may make sense to standardize all developers on that language.
We should probably put on our Reality Glasses for this discussion. It's not just Syntactic Sugar going on here.
You will find that you can write code very quickly in Visual Basic.NET. That is largely due to some features that it has that C# does not yet provide: namely, the My namespace, which provides a plethora of functionality that C# developers have to frequently code by hand. (And that's a damned shame, if you ask me.)
I code in both languages every day. Coding event handlers for forms in Visual Basic is a snap, and it's VERY obvious what methods handle which events. It's not always as clear in C#. On the other hand, you can't always be as explicit in Visual Basic as you want to be, because Visual Basic does so much of the work for you. C# has the advantage of just getting the heck out of your way, and letting you get down to the nuts and bolts. Quite often, that's extremely liberating.
VB will let you invoke static/shared methods on an object instance. C# won't. You'll learn that the hard way when you try to port your code. C# will complain about unreachable code; VB doesn't care one way or the other.
But under the hood, when you get right down to it, it's all .NET. It all compiles down to MSIL. There will be minor differences. Visual Basic, for example, doesn't care about the case-sensitivity of names, where C# does. And the big gotcha there is that the CLR does as well. You'll realize that when you try to use reflection. Does that mean you shouldn't use VB? Nope. Just make sure you case things consistently -- especially your namespaces. (Namespace "My" and namespace "my" are two completely different namespaces to C# and the CLR, but they're the same to VB.)
Choose the language that makes you most productive, that reduces ramp-up time and maintenance costs. You may find that that means working with both languages. (We do!)
EDIT TO ADDRESS OP'S EDIT:
Refactoring tools are available for both languages.
Automated unit testing tools are equally applicable.
3rd party controls are going to be available for both languages because they're compiled down to MSIL.
Now, for IDE productivity tools, the one thing that C# has at this time that VB doesn't is StyleCop. That may change soon (and I hope it does), but I don't view it as a roadblock by any stretch of the imagination.
This is personal experience mixed with workplace lore:
VB.NET is capable of being little more nimble, compared to C#, because there isn't a standards committee (except for any that may exist at Microsoft).
Most of the Google-able code hackery out there is done in C#, and most of the best resource books provide code samples in C# only.
VB.NET is tainted with a history of VB being accessible to even the most incapable of developers. This is unfair, imho, because VB.NET is much more a "real" language. But the taint isn't going to be washed away any time soon, and "real" programmers still generally despise it.
As for real life - I code in my own time in C# and VB.NET at work. I believe that because so much of the code one writes for .NET is calls against the framework objects, the differences are actually quite small. If you can declare variables in both languages you're 80% to being portable. If you understand the framework, the syntax of the languages is a small obstacle.
EDIT to directly answer your question: We happily use both (though mainly VB.NET) and haven't ever had any problems. We use Visual Studio which allows us to pretty freely mix code files/assemblies. I would encourage you not to limit to a single language - I think some diversity is good for the brain.
My workplace had traditionally been a VB.Net shop, but a decision was made a couple years ago to switch to C#. This happened mostly because the VB developers had either left or moved into other positions and most of the new hires preferred C#. We still have a large legacy VB.Net code base, but all new development is being done in C#.
I don't think there's a strong technical reason to choose one language over the other, as they are pretty equivalent in functionality, but I do feel there are some valid reasons to choose one type of developer over the other. While I believe VB and C# are equal, there's is the unfortunate perception that C# developers are better than VB developers. While there is some justification for this, it's overblown. (It was more applicable in the C++/VB days.) That said, the perception exists. This does cause some talented developers to avoid and bash VB (though they usually do so from ignorance). I do think it's harder to hire developers into a VB shop than visa versa, because a C# developer will often balk at the idea of having to use VB, but VB developers usually aren't as opposed to using C#. There is one significant disadvantage to choosing C# over VB and that's that C# developers generally get paid more.
In my experience, the best developers welcome using both languages. The more languages you know, the better.
After tracking your question for a little bit and noting your edit, I have to wonder if you're fishing a little bit...
Either way, I think it's fairly obvious that at least the latest third-party tools favor C#. I, like the other responders, code VB for work and prefer C# for other development. I have definitely noticed that the documentation for many third-party addins/plugins and in some cases the products themselves favor C#. ReSharper, even though 4.5 has better VB support, is still vastly more comprehensive when using C#. And other frameworks, like Fluent NHibernate, don't support VB at all. So for tooling, especially when considering late-breaking stuff, I believe that C# wins. Not to mention the fact that C# got a few new features in 3.0 that won't be available until VB 10 makes a wide release.
I still agree whole-heartedly with the others; if you can do it in C#, you can do it in VB. It's all the same CLR, in the end.
I'd say given that there are "some VB.NET developers and some C# developers," there really is very little benefit to forcing everyone to use one language. Frankly even a VB.NET developer who's never looked at C# should be able to read C# code with no more than a brief introduction to the syntax, assuming he/she has a reasonable understanding of the .NET framework; and a C# developer should be able to do the same with VB.NET.
(I should also add: this is assuming everyone has access to a development environment in which the .NET languages can co-exist harmoniously -- e.g., VS2005, VS2008, etc., as opposed to one of the Express Editions, which as far as I know don't allow multi-language solutions.)
Don't fall for the "most examples / books are written for C#". Working out how to apply a C# example to VB.NET is trivial -- you'll have more trouble trying to understand what the moron who wrote the example / book is trying to do and what their hideous coding (un)convention is all about than you will mentally flipping C# syntax to VB syntax.
Also I'd say don't worry about whether you hire C# or VB.NET programmers: if they are any good at all then they won't have a problem with reading / writing both languages.
We use both here, and after a little resistance from some (we were using C++ before) have settled down fine. As I had predicted, the hardest thing for our team was (and probably still is) the conversion from MFC to .NET, not the language used to access the libraries.
FWIW our main split is VB.NET for UI code, and C# for backend / database / computation code.
C# and VB.net are the same with a different syntax. You can convert from C# to VB.net and back very easily.
VB.net does have a few extra advantages that C# does not, such as inline XML.
Most places have C# because its the more popular language.
I started out as a VB developer so naturally I migrated to VB.Net when I first worked with .Net. In fact my first .Net application was made in VB.Net too. But I tried out C# and found myself liking it better in a matter of weeks.
So I made some of that app in C# (some libraries) and it didn't hurt me. Now though I hate going back to the older VB.Net code and working on it. I really wish I could change it all to C# somehow.
That's not going to happen.
So what I am telling you here is, irrelevant of what language you choose (VB/C#) stick to it. Don't do mixed language development unless you have a compelling reason I can't think of yet :)
The advantage of standardizing on a single language is that basically everyone will have 1/2 as much to learn. I think it's better to spend the time learning more features of .NET, within a single language, rather than learning 1/2 the features in both.
As far as hiring goes, it does not really restrict you as a good VB or C# programmer should be able to switch to the other language without difficulty (or else they aren't really a good programmer :)