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Easiest way to Implement Scripting to WPF C# Visual Studio 2015

I'd like some help in how to add scripting support to a WPF C# project I'm doing on Visual Studio 2015. One of the things I'd like to do is to be able to change User Control properties within that script. I've being trying Roslyn C#, and I read some stuff about IronPython and PowerShell Tools. But, all that information is not really helping.
So, do you have a simple answer? Like, the easiest way to execute scripts in Visual Studio 2015 C# WPF Application, that are able to change properties of User Controls within the project?
Any help would be appreciated.
Thanks,
Lucas.

T4 templates can help but they are less extensible than lets say Roslyn.

I found a great post on how to easily implement IronPython and how to access User Controls within the scripts in Python, so you can there change different Control properties, and even create them! Here's the link:http://www.codeproject.com/Articles/602112/Scripting-NET-Applications-with-IronPython

I think it should be quite simple to embed powershell or F# interactive in an application and there are lots of examples when we search the web for this. The question is only are we comfortable writing scripts in Powershell and F#?
In my application I provide a C# editor and compile scripts as static methods (which I uses as functions) using the standard .Net compiler API's which are installed with the framework (Microsoft.Csharp, System.CodeDom). This generates a temporary dll and perhaps can not be properly termed a script. The implementation is straight forward and more or less what you expect - I have to provide a way for the users to specify references and namespaces, then generate a source file, compile it to an assembly and then call members of the static class. This above technique works well because the application has extension points that are well adapted to user defined code with a certain well defined structure (you might have similar well defined needs and perhaps full scripting is not necessary).
On the other hand, I am considering providing a "super user" console where the application can be driven by script, and in this case, I will use either Powershell or F-sharp interactive (I'm leaning towards F#). I don't think the implementation is particularly complex, but these are things that can easily bring the application down or corrupt application data if it is not well controlled - and it is unlikely that my users will profit from scripting as it is a programmer environment.

Regionalisation Design Patterns in C#

I am currently working on creating a GUI for an interface that will be used in several languages.
The environment I am working in is Unity 4.2 with Mono C#. The application must remain very cross platform compatible (including web, ios, Linux, windows).
What I am trying to achieve is a nice way of handling the multiple languages, allowing for the easy addition of an extra language, or an extra field. If I were working in ruby or python, I believe this may be a decent solution;
class RegionalDB:
def __init__(self):
# Maybe connect to a data source such as a db, or files
def set_language(self, lang):
# Verify we have this lang, error if not
# Set an attribute on self for every field entry in this language
text = RegionalDB()
text.set_language('de')
print text.exit_button
The above method would allow me to use the powerful features of python objects being able to dynamically assign members at runtime. The code above would print, in German, the text that was in the "exit_button" field of the data source. In ruby I could do similar, or I could use the attribute_missing function to query the data source directly instead of assigning all variables in memory at once to the object.
Unfortunately C#'s Reflection code is not quite as elegant as the scripts mentioned above. So my issues are as follows;
Creating an elegant, maintainable, regionalisation tool in a compiled, strongly typed language.
Storing the data for the languages in an effective manner using unity
With issue 1. I have been unable to find a design pattern, or much information at all to be honest.
Issue 2. I believe can be solved with some unity editor programming, but I have not touched this topic much and am open to suggestions.
So in question form;
Does anybody know of any design patterns that would work well with C# for regionalisation
Any suggestions on a way forward with an interface/storage mechanism in the unity editor
Thanks.
P.S. I must be able to change language at runtime

There are a lot of C# apps out there which already have l10n support.
I would divide them in three types:
Resources-based internationalization: Texts are stored in XML files. This is the Microsoft way.
PO-based internationalization: Using the long-stablished gettext technology which includes many Unixy tools to deal with updating original texts and translations. You can see how this works by taking a look at the code of some Mono desktop app (i.e.: Banshee), and look for the Catalog.GetString() calls, which use the Mono.Posix assembly as a linked reference.
Vernacular-based internationalization: used in mobile apps to abstract each mobile-platform localization details and have a common method across all.
In my particular opinion, the best and most modern method is the latter. But if you're targetting a desktop app, I guess you can create/contribute a new Vernacular backend to fit this purpose.

JSIL vs Script# vs SharpKit

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.

Creating an interactive shell for .NET apps and embed scripting languages like python/iron python into it

I was learning python using the tutorial that comes with the standard python installation. One of the benefits that the author states about python is "maybe you’ve written a program that could use an extension language, and you don’t want to design and implement a whole new language for your application" - My question is how would i go about designing a program (using c#) that can be extended using Python interactively(for this to be possible, i would imagine that i would need to create some sort of a "shell" or "interactive" mode for the .net program) ?
Are there any pointers on how to design .NET programs that have an interactive shell. I would then like to use python script in the shell to "extend" or interact with the program.
EDIT: This question partly stems from the demo give by Miguel de Icaza during PDC 2008 where he showed the interactive csharp command prompt, C# 4.0 i think also has this "compiler as a service" feature. I looked at that and thought how cool would it be to design a windows or web program in .NET that had a interactive shell.. and a scripting language like python could be used to extend the features provided by the program.
Also, i started thinking about this kind of functionality after reading one of Steve Yegge's essays where he talks about systems that live forever.

This sounds like a great use of IronPython.
It's fairly easy to set up a simple scripting host from C# to allow calls into IronPython scripts, as well as allowing IronPython to call into your C# code. There are samples and examples on the CodePlex site that show how to do this very thing.
Another good site for examples and samples is ironpython.info
And here is a page dedicated to an example answering your very question, albeit in a generic DLR-centric way -- this would allow you to host IronPython, IronRuby, or whatever DLR languages you want to support.
I've used these examples in the past to create an IronPython environment inside a private installation of ScrewTurn Wiki - it allowed me to create very expressive Wiki templates and proved to be very useful in general.

I was looking solution for the same problem, and found IronTextBox: http://www.codeproject.com/KB/edit/irontextbox2.aspx
It needs a little tuning for current versions, but seems to be everything I needed. First made it compile, and then added variables I wanted to access from shell to the scope.

Python as an extension language is called "Embedding Python".
you can call a python module from c++ by bascially calling the python intepreter and have it execute the python source. This is called embedding.
It works from C and C++, and will probably work just as well from C#.
And no, you do not need any kind of "shell". While Python can be interactive, that's not a requirement at all.

Here is a link to a blog post about adding IronRuby to script a C# application.
http://blog.jimmy.schementi.com/2008/11/adding-scripting-to-c-silverlight-app.html
The principles would also work well for using IronPython.

If your goal is to avoid learning a new language you can use CSScript.Net and embedded scripts written in C# or VB into you application. With CSScript you get full access to the CLR. Three different models of script execution are supported so that you can execute script that refers to objects in your current app domain, execute using remoting, or execute as a shell.
Currently I am using CCScript as "glue" code for configuring application objects somewhat similar to using Boo.
This link tasks you to a code project article that provides a good overview.

I don't know what you mean with
"extend" or interact with the program
so I can't answer your question. Can you give an example?
There is an open source interactive C# shell in mono: http://www.mono-project.com/CsharpRepl
When you like python, .Net and language extension, you will probably like Boo over Iron python. Boo comes with an open source interactive shell too.
I disagree with
"you don’t want to design and
implement a whole new language for
your application"
It's not as hard as it used to be to create a simple DSL. It won't take you days to implement, just hours. It might be an interesting option.

Running scripts inside C#

I want to run javascript/Python/Ruby inside my application.
I have an application that creates process automatically based on user's definition. The process is generated in C#. I want to enable advanced users to inject script in predefined locations. Those scripts should be run from the C# process.
For example, the created process will have some activities and in the middle the script should be run and then the process continues as before.
Is there a mechanism to run those scripts from C#?

Basically, you have two problems: how to define point of injections in your generated code, and how to run python / ruby / whatev scripts from there.
Depending on how you generate the process, one possible solution would be to add a function to each possible point of injection. The function would check, whether the user has associated any scripts with given points, and if so, runs the script by invoking IronPython / IronRuby (with optionally given parameters).
Disadvantages include: limited accessibility from the scripts to the created process (basically, only variables passed as parameters could be accessed); as well as implementation limits (IronPython's current version omits several basic system functions).

Look into IronPython and IronRuby -- these will allow you to easily interoperate with C#.

You can compile C# code from within a C# application using the CSharpCodeProvider class.
If the compile succeeds you can run the resulting assembly as returned via the CompiledAssembly property of the CompilerResults class.

Awesome C# scripting language - Script.Net

.NET has a scripting language including runtime engine in PowerShell which can be embedded in any .NET application.

You can compile C# code "on the fly" into an in-memory assembly. I think this is possible with IronPython and IronRuby as well. Look at the CodeDomProvider.CreateProvider method.
If you need to run scripts a lot, or if your process runs for a long time, you might want to load these assemblies into another AppDomain. And unload the AppDomain after you're done with the script. Otherwise you are unable to remove them from memory. This has some consequenses on the other classes in your project, because you have to marshall all calls.

Have you thought about Visual Studio for Applications? I haven't heard much about it since .NET 1.1, but it might be worth a look.
http://msdn.microsoft.com/en-us/library/ms974548.aspx

I've done exactly this just recently - allowed run-time addition of C# scripting.
It's not hard at all, and this article:
http://www.divil.co.uk/net/articles/plugins/scripting.asp
is a very useful summary of the details.

One of Microsoft's solutions to JavaScript in C# is ClearScript,
which uses V8, Chrom browser's JavaScript engine. Check its short FAQtorial for code samples.
It has excellent two-way integration - iterator/enumerator, output parameters, optional parameters, parameter arrays, delegate, task/promise/async/await, bigint, and more.
Apart from that, I think the most distinguishing feature is that it does not depend on Rosyln or Dynamic Language Runtime. This can be good or bad - good because there may be a lot less dependencies (depending on your project's target), bad because you need to bundle the native, platform-dependent V8 dll.
If that is ok, you get to enjoy cutting edge JavaScript / ECMAScript. Everything you get on Chrome, or 98% ES6 as of 2022 Feb, plus several extensions. Speed is as fast as Chrome, obviously, so you get the best of both Google and Microsoft.