Execute JavaScript from within a C# assembly

Question

I'd like to execute JavaScript code from within a C# assembly and have the results of the JavaScript code returned to the calling C# code.

It's easier to define things that I'm not trying to do:

• I'm not trying to call a JavaScript function on a web page from my code behind.

• I'm not trying to load a WebBrowser control.

• I don't want to have the JavaScript perform an AJAX call to a server.

What I want to do is write unit tests in JavaScript and have then unit tests output JSON, even plain text would be fine. Then I want to have a generic C# class/executible that can load the file containing the JS, run the JS unit tests, scrap/load the results, and return a pass/fail with details during a post-build task.

I think it's possible using the old ActiveX ScriptControl, but it seems like there ought to be a .NET way to do this without using SilverLight, the DLR, or anything else that hasn't shipped yet. Anyone have any ideas?

update: From Brad Abrams blog

namespace Microsoft.JScript.Vsa
{
    [Obsolete("There is no replacement for this feature. " +
              "Please see the ICodeCompiler documentation for additional help. " +
              "http://go.microsoft.com/fwlink/?linkid=14202")]

Clarification: We have unit tests for our JavaScript functions that are written in JavaScript using the JSUnit framework. Right now during our build process, we have to manually load a web page and click a button to ensure that all of the JavaScript unit tests pass. I'd like to be able to execute the tests during the post-build process when our automated C# unit tests are run and report the success/failure alongside of out C# unit tests and use them as an indicator as to whether or not the build is broken.

Answer 1

The code should be pretty self explanitory, so I'll just post that.

<add assembly="Microsoft.Vsa, Version=8.0.0.0, Culture=neutral, PublicKeyToken=B03F5F7F11D50A3A"/></assemblies>

---

using Microsoft.JScript;

public class MyClass {

    public static Microsoft.JScript.Vsa.VsaEngine Engine = Microsoft.JScript.Vsa.VsaEngine.CreateEngine();

    public static object EvaluateScript(string script)
    {
        object Result = null;
        try
        {
            Result = Microsoft.JScript.Eval.JScriptEvaluate(JScript, Engine);
        }
        catch (Exception ex)
        {
            return ex.Message;
        }

        return Result;
    }

    public void MyMethod() {
        string myscript = ...;
        object myresult = EvaluateScript(myscript);
    }
}