How to pass a generic list to a dynamically compiled C# code?

I want to let the user to write a block of code as text, compile it on the fly, execute it on a collection which I obtain from a data source and get the result.

I have been tying to pass a generic list as a parameter to the dynamically compiled code, but I could not figure out a way. Following is my code:

//User writes this code in a textbox and executes
var executeCode = @"//this line doesn't work because I don't know the type
                            MessageBox.Show(Parameters[0].Count());
                            //following works fine
                            var t = new List<string>{""asd"", ""xyz""};
                            var a = t.Select(x => x).First();
                            MessageBox.Show(a); 
                            return (object) a;";

#region template Code
executeCode = @"
                using System;
                using System.IO;
                using System.Windows.Forms;
                using System.Linq;
                using System.Collections.Generic;

                namespace MyNamespace {
                public class MyClass {

                public object DynamicCode(params object[] Parameters) {
                " + executeCode +
                "}   }    }";
#endregion template Code

var references = new[] { "System.dll", "System.Core.dll", "System.Windows.Forms.dll" };

var compilerParams = new CompilerParameters
            {
                GenerateInMemory = true,
                TreatWarningsAsErrors = false,
                GenerateExecutable = false,
                CompilerOptions = "/optimize"
            };
        compilerParams.ReferencedAssemblies.AddRange(references);

        var provider = new CSharpCodeProvider();
        var compile = provider.CompileAssemblyFromSource(compilerParams, executeCode);

        if (compile.Errors.HasErrors)
        {
            var text = compile.Errors.Cast<CompilerError>()
                              .Aggregate("Compile Error: ", (current, ce) => current + ("rn" + ce.ToString()));
            throw new Exception(text);
        }

        // execute the compiled code

        var assembly = compile.CompiledAssembly;
        var myObject = assembly.CreateInstance("MyNamespace.MyClass");
        if (myObject == null)
        {
            MessageBox.Show("Couldn't load class.");
            return;
        }

        var sampleList = new List<string> { "abcd", "bcd" };
        var codeParams = new object[] { sampleList };

        try
        {
            var loResult = myObject.GetType().InvokeMember("DynamicCode",BindingFlags.InvokeMethod, null, myObject, codeParams);
            MessageBox.Show("Method Call Result:\r\n\r\n" + loResult, "Compiler Demo", MessageBoxButtons.OK, MessageBoxIcon.Information);
        }
        catch (Exception loError)
        {
            MessageBox.Show(loError.Message, "Compiler Demo", MessageBoxButtons.OK, MessageBoxIcon.Information);
        }

In the above code I just pass a string list. But I will replace it with an object. User will write Linq queries to filter the collection, which I compile on the fly and return the result.

Any pointers on this will be really helpful. (I use C# 4.5)