Develop Reference

C# code completion with NRefactory 5

I just found out about NRefactory 5 and I would guess, that it is the most suitable solution for my current problem. At the moment I'm developing a little C# scripting application for which I would like to provide code completion. Until recently I've done this using the "Roslyn" project from Microsoft. But as the latest update of this project requires .Net Framework 4.5 I can't use this any more as I would like the app to run under Win XP as well. So I have to switch to another technology here.
My problem is not the compilation stuff. This can be done, with some more effort, by .Net CodeDomProvider as well. The problem ist the code completion stuff. As far as I know, NRefactory 5 provides everything that is required to provide code completion (parser, type system etc.) but I just can't figure out how to use it. I took a look at SharpDevelop source code but they don't use NRefactory 5 for code completion there, they only use it as decompiler. As I couldn't find an example on how to use it for code completion in the net as well I thought that I might find some help here.
The situation is as follows. I have one single file containing the script code. Actually it is not even a file but a string which I get from the editor control (by the way: I'm using AvalonEdit for this. Great editor!) and some assemblies that needs to get referenced. So, no solution files, no project files etc. just one string of source code and the assemblies.
I've taken a look at the Demo that comes with NRefactory 5 and the article on code project and got up with something like this:
var unresolvedTypeSystem = syntaxTree.ToTypeSystem();
IProjectContent pc = new CSharpProjectContent();
// Add parsed files to the type system
pc = pc.AddOrUpdateFiles(unresolvedTypeSystem);
// Add referenced assemblies:
pc = pc.AddAssemblyReferences(new CecilLoader().LoadAssemblyFile(
System.Reflection.Assembly.GetAssembly(typeof(Object)).Location));
My problem is that I have no clue on how to go on. I'm not even sure if it is the right approach to accomplish my goal. How to use the CSharpCompletionEngine? What else is required? etc. You see there are many things that are very unclear at the moment and I hope you can bring some light into this.
Thank you all very much in advance!

I've just compiled and example project that does C# code completion with AvalonEdit and NRefactory.
It can be found on Github here.

Take a look at method ICSharpCode.NRefactory.CSharp.CodeCompletion.CreateEngine. You need to create an instance of CSharpCompletionEngine and pass in the correct document and the resolvers. I managed to get it working for CTRL+Space compltition scenario. However I am having troubles with references to types that are in other namespaces. It looks like CSharpTypeResolveContext does not take into account the using namespace statements - If I resolve the references with CSharpAstResolver, they are resolved OK, but I am unable to correctly use this resolver in code completition scenario...
UPDATE #1:
I've just managed to get the working by obtaining resolver from unresolved fail.
Here is the snippet:
var mb = new DefaultCompletionContextProvider(doc, unresolvedFile);
var resolver3 = unresolvedFile.GetResolver(cmp, loc); // get the resolver from unresolvedFile
var engine = new CSharpCompletionEngine(doc, mb, new CodeCompletionBugTests.TestFactory(resolver3), pctx, resolver3.CurrentTypeResolveContext );
Update #2:
Here is the complete method. It references classes from unit test projects, sou you would need to reference/copy them into your project:
public static IEnumerable<ICompletionData> DoCodeComplete(string editorText, int offset) // not the best way to put in the whole string every time
{
var doc = new ReadOnlyDocument(editorText);
var location = doc.GetLocation(offset);
string parsedText = editorText; // TODO: Why there are different values in test cases?
var syntaxTree = new CSharpParser().Parse(parsedText, "program.cs");
syntaxTree.Freeze();
var unresolvedFile = syntaxTree.ToTypeSystem();
var mb = new DefaultCompletionContextProvider(doc, unresolvedFile);
IProjectContent pctx = new CSharpProjectContent();
var refs = new List<IUnresolvedAssembly> { mscorlib.Value, systemCore.Value, systemAssembly.Value};
pctx = pctx.AddAssemblyReferences(refs);
pctx = pctx.AddOrUpdateFiles(unresolvedFile);
var cmp = pctx.CreateCompilation();
var resolver3 = unresolvedFile.GetResolver(cmp, location);
var engine = new CSharpCompletionEngine(doc, mb, new CodeCompletionBugTests.TestFactory(resolver3), pctx, resolver3.CurrentTypeResolveContext );
engine.EolMarker = Environment.NewLine;
engine.FormattingPolicy = FormattingOptionsFactory.CreateMono();
var data = engine.GetCompletionData(offset, controlSpace: false);
return data;
}
}
Hope it helps,
Matra

NRefactory 5 is being used in SharpDevelop 5. The source code for SharpDevelop 5 is currently available in the newNR branch on github. I would take a look at the CSharpCompletionBinding class which has code to display a completion list window using information from NRefactory's CSharpCompletionEngine.

NUnit get results programmatically during run session

again i am trying to do something and not sure if it is possible. i want to run my Nunit tests and after each test is run, i want to output the result to my ui. the ui is custom and is used by my test team to run and see test results. when i say it is used, it is not developed yet (fully) :) - bringing me to this question.
my code so far
TestPackage package = new TestPackage(path);
RemoteTestRunner remote = new RemoteTestRunner();
remote.Load(package);
TestResult result = remote.Run(new NullListener(), TestFilter.Empty, true, LoggingThreshold.All);
while (remote.Running)
{
// want to capture results here
if (result.HasResults)
// i can never get here while test is running
}

How about dumping the results as XML into shared location. And then your UI can parse/pick up from that location
Also try to use common XML schema so that you can easily serialize/deserialize back from XML to C# object and vice versa
We have done smth similar in the past and above scenario has worked quite well

Changing environment variables of the calling process

This one seems trivial but the answer has eluded me for a few days now.
I have a Windows batch file, that calls a C# program to do an extra verification that cannot be done in a batch file. After the verification is complete I need to return a status and a string back to the calling shell.
Now the return value is trivial and my C# console app simply sets a return value (exit code if you will). And I thought the string will also be a piece of cake. I attempted to define a new shell variable using the:
Environment.SetEnvironmentVariable("ERR", "Some text");
This call should (and does) define a shell variable within the current process - that is the very C# process that created the variable. The value is lost as soon as the C# app terminates and the shell that created the C# app knows nothing about the variable. So... A call with no particular use... At all... Unless perhaps if I created a child process from the C3 app, perhaps it would inherit my variables.
The EnvironmentVariableTarget.Machine and EnvironmentVariableTarget.User targets for the SetEnvironmentVariable call don't solve the problem either, as only a newly created process will get these new values from the registry.
So the only working solution I can think of is:
write to stdout
write to a file
encode extra meaning into the return value
The first two are a bit ugly and the last one has its limitations and problems.
Any other ideas (how to set a shell variable in the parent process)? Maybe such shell variable modifications are a security concern (think PATH)...
Thank-you for your time.

I had the same problem as Ryan and the only thing that came to my mind as a work-around was to write a batch in error out to set the variable and to call it from the batch.
ConsoleApplication1.exe:
'put some sensible code here
'put result in variable myResult
Dim myResult As String = Guid.NewGuid().ToString("D").ToUpperInvariant()
Console.WriteLine("Normal output from the consonle app")
Console.Error.WriteLine("#ECHO OFF")
Console.Error.WriteLine("SET zzzResult={0}", myResult)
Test.cmd (the calling batch):
#ECHO OFF
:Jump to folder of batch file
PUSHD %~d0%~p0
:Define a temp file
SET zzzTempFile=%TEMP%\TMP%Random%.CMD
:Call .NET console app
ConsoleApplication1.exe 2>%zzzTempFile%
:Call the generated batch file
CALL %zzzTempFile%
:Clean up temp file
DEL %zzzTempFile%
:Clean up variable
SET zzzTempFile=
:Do something with the result
ECHO Yeah, we finally got it!
ECHO:
ECHO The value is "%zzzResult%".
ECHO:
:Clean up result variable
SET zzzResult=
:Go back to original folder
POPD
That should do the trick. And yes, I do know this is an old post and Ryan is solving other issues by now, but there might be still somebody else out there having the same problem...

What you are asking is to be able to arbitrarily write to the memory space of a running process. For good reason, this is not possible without SeDebugPrivilege.
Any of the three solutions you list will work. Stdout is the standard way to communicate with a batch script.
By the way, you're writing a Windows batch file. I'm pretty sure the ship has already sailed on "a bit ugly".

If you want to put a value of some output into a variable in the batch you can use the following construct:
FOR /F "usebackq tokens=4 delims=\[\] " %i IN (`ver`) DO set VERSION=%i
ECHO %VERSION%
Output on my OS:
6.1.7601
'usebackq' means we are using back quotes which gives the ability to use a fileset in the command quoted with double quotes. You may not need this. 'tokens' means the index in the resulting string array to select (it can be a range M-N). If you need to skip lines use 'skip=X'). 'delims' are the string separators to use (like string-Split() in .Net).
You will put your console app instead of 'ver' and adapt the delimiters and tokens to match your specific output. If you have more variables to fill you will need to make the if a bit more complex but that should make a good start.

My BAT is a bit rusty, but I think it's possible to retrieve the 'exit' code from processes you've run externally, perhaps via %ERRORLEVEL%. If that's the case, make sure to exit your program via
Environment.Exit(123); // where 123 = error code
You can't add any messages, so you'll have to do that in the .bat file.
If this isn't the case, stdout is probably the best way.

After stumbling on this myself as well recently, I came up with this approach. What I did is run the bat file using the Process class, i.e.
// Spawn your process as you normally would... but also have it dump the environment varaibles
Process process = new Process();
process.StartInfo.FileName = mybatfile.bat;
process.StartInfo.Arguments = #"&&set>>envirodump.txt";
process.StartInfo.UseShellExecute = false;
process.StartInfo.RedirectStandardOutput = true;
process.StartInfo.RedirectStandardError = false;
process.Start();
string output = process.StandardOutput.ReadToEnd();
process.WaitForExit();
// Read the environment variable lines into a string array
string[] envirolines = File.ReadAllLines("envirodump.txt");
File.Delete("envirodump.txt");
// Now simply set the environment variables in the parent process
foreach(string line in a)
{
string var = line.Split('=')[0];
string val = line.Split('=')[1];
Environment.SetEnvironmentVariable(var, val);
}
This seems to have worked for me. It's not the cleanest approach, but will work in a bind. :)

IronPython and Nodebox in C#

My plan:
I'm trying to setup my C# project to communicate with Nodebox to call a certain function which populates a graph and draws it in a new window.
Current situation: [fixed... see Update2]
I have already included all python-modules needed, but im still getting a
Library 'GL' not found
it seems that the pyglet module needs a reference to GL/gl.h, but can't find it due to IronPython behaviour.
Requirement:
The project needs to stay as small as possible without installing new packages. Thats why i have copied all my modules into the project-folder and would like to keep it that or a similar way.
My question:
Is there a certain workaround for my problem or a fix for the library-folder missmatch.
Have read some articles about Tao-Opengl and OpenTK but can't find a good solution.
Update1:
Updated my sourcecode with a small pyglet window-rendering example. Problem is in pyglet and referenced c-Objects. How do i include them in my c# project to be called? No idea so far... experimenting alittle now. Keeping you updated.
SampleCode C#:
ScriptRuntimeSetup setup = Python.CreateRuntimeSetup(null);
ScriptRuntime runtime = new ScriptRuntime(setup);
ScriptEngine engine = Python.GetEngine(runtime);
ScriptSource source = engine.CreateScriptSourceFromFile("test.py");
ScriptScope scope = engine.CreateScope();
source.Execute(scope);
SampleCode Python (test.py):
from nodebox.graphics import *
from nodebox.graphics.physics import Vector, Boid, Flock, Obstacle
flock = Flock(50, x=-50, y=-50, width=700, height=400)
flock.sight(80)
def draw(canvas):
canvas.clear()
flock.update(separation=0.4, cohesion=0.6, alignment=0.1, teleport=True)
for boid in flock:
push()
translate(boid.x, boid.y)
scale(0.5 + boid.depth)
rotate(boid.heading)
arrow(0, 0, 15)
pop()
canvas.size = 600, 300
def main(canvas):
canvas.run(draw)
Update2:
Line 139 [pyglet/lib.py] sys.platform is not win32... there was the error. Fixed it by just using the line:
from pyglet.gl.lib_wgl import link_GL, link_GLU, link_WGL
Now the following Error:
'module' object has no attribute '_getframe'
Kind of a pain to fix it. Updating with results...
Update3:
Fixed by adding following line right after first line in C#-Code:
setup.Options["Frames"] = true;
Current Problem:
No module named unicodedata, but in Python26/DLLs is only a *.pyd file`. So.. how do i implement it now?!
Update4:
Fixed by surfing: link text and adding unicodedata.py and '.pyd to C# Projectfolder.
Current Problem:
'libGL.so not found'... guys.. im almost giving up on nodebox for C#.. to be continued
Update5:
i gave up :/ workaround: c# communicating with nodebox over xml and filesystemwatchers. Not optimal, but case solved.

-X:Frames enables the frames option as runtime (it slows code down a little to have access to the Python frames all the time).
To enable frames when hosting you just need to do:
ScriptRuntimeSetup setup = Python.CreateRuntimeSetup(new Dictionary<string, object>() {
{ "Frames", true }
});
Instead of the null that you're passing now. That's just creating a new dictionary for the options dictionary w/ the contents "Frames" set to true. You can set other options in there as well and in general the -X:Name option is the same here as it is for the command line.

Embedding Perl Interpreter

just downloaded ActivePerl. I want to embed the perl interpreter in a C# application (or at least call the perl interpreter from C#). I need to be able to send send out data to Perl from C#, then receive the output back into C#.
I just installed ActivePerl, and added MS Script Control 1.0 as a reference. I found this code on the internet, but am having trouble getting it to work.
MSScriptControl.ScriptControlClass Interpreter = new MSScriptControl.ScriptControlClass();
Interpreter.Language = #"ActivePerl";
string Program = #"reverse 'abcde'";
string Results = (string)Interpreter.Eval(Program);
return Results;
Originally, it had 'PerlScript' instead of 'ActivePerl', but neither work for me. I'm not entirely sure what Interpreter.Language expects. Does it require the path to the interpreter?
Solved... I'm not sure how, but when I changed it back to PerlScript it works now. Still, I would like to know if MSScript Control is using ActivePerl or another interpreter.

You can run an external program as Maxwell suggests, in which case the external program can be Perl or anything else. It might be easier to use temp files to send the input data and get the output, but that depends on how the external program expects to get its data.
The alternative, which is what I think you're looking for, is to use the PerlNET compiler that comes with ActiveState's Perl Dev Kit. It lets you add a class wrapper around the Perl code so you can expose it to C# just like any C# class. It's fairly simple to use; you add POD comments to your Perl code to specify the method names and signatures to expose, including type information, then you compile your Perl module into a DLL .NET assembly. Once that's done you can reference the assembly from any .NET program, construct an object from your Perl class, and call its methods.

I am not sure about the script control but I have done a similar thing where I had to 'embed' spamassasin (which is a Perl program). I basically used the Process to do the job. Something along the lines of:
var proc = new Process
{
StartInfo =
{
FileName = "perl",
WorkingDirectory = HttpRuntime.AppDomainAppPath,
Arguments = " myscript.pl arg1 arg2",
RedirectStandardOutput = true,
RedirectStandardError = true,
RedirectStandardInput = true,
UseShellExecute = false
}
};
proc.Start();
proc.StandardInput.BaseStream.Write... // feed STDIN
proc.StandardOutput.Read... // Read program output
var procStdErr = proc.StandardError.ReadToEnd(); // errors
proc.StandardError.Close();
proc.StandardOutput.Close();
proc.WaitForExit(3000);
int exitCode = proc.ExitCode;
proc.Close();
This obviously not just Perl specific and it has the process creation overhead, so if you are running your script too often probably you need to think of a different solution.