In-Game scripting works in Editor (Try it!) - But Not Build

The Idea

• want players to be able to interact with the game through C# scripting. Everything works in the editor (go ahead an try it), but not when I "build" the game. This is the error (exception message) I see:**

  ---

  The Error Message

  n exception was thrown by the type initializer for Mono.CSharp.CSharpCodeCompiler System at Microsoft.CSharp.CSharpCodeProvider.CreateCompiler () [0x00000] in :0 at System.CodeDom.Compiler.CodeDomProvider.CompileAssemblyFromSource (System.CodeDom.Compiler.CompilerParameters options, System.String[] fileNames) [0x00000] in :0 at ScriptEditor.Compile () [0x00000] in :0

  ---

  The Code

  o Run this script in your game:

  1. Create a C# script file "ScriptEditor.cs "

  2. Paste this code.

  3. Attach to any game object

  4. In Build Settings->Player Settings, change ".NET 2.0 Subset" to ".NET 2.0"

     ---

     using UnityEngine; using System; using System.Text; using System.Collections; using System.Reflection; using System.CodeDom; using System.CodeDom.Compiler; using Microsoft.CSharp;

     ///

     /// ScriptEditor.cs (Attach this to any game object) /// Useage Notes: /// For this to run, you MUST: /// 1. Go to File-->Build Settings... /// 2. Click "Player Settings..." /// 3. "Other Settings" /// 4. "Optimization"-->"API Compatability Level" /// 5. Change from ".NET 2.0 Subset" --> ".NET 2.0" ///

     public class ScriptEditor : MonoBehaviour {

       void Update()
          {
              // Dont run our script until it has been COMPILED successfully.
              if(myScript_Type == null || myScript_Instance == null) return;      
              
              // Run the script's Update() function
              myScript_Type.InvokeMember("Update",BindingFlags.InvokeMethod | BindingFlags.Instance | BindingFlags.Public, null, myScript_Instance, null);
              
              // Read the scripts "readme" variable.
              PropertyInfo readmePropertyInfo = myScript_Type.GetProperty("readme");        // Source: http://www.csharp-examples.net/reflection-examples/
              readme = (string)readmePropertyInfo.GetValue(myScript_Instance, null);
          }
          
          private string scriptText = 
      @"using System;
      using System.Collections.Generic;
      
      public class MyScript
      {
          public string readme {get;set;}  // Our unity program will read this variable.
          private int counter = 0;    
      
          public MyScript() // Constructor
          {
              readme = """";
          }
      
          public void Update()  // Our unity game will run this function.
          {
              counter++;        
              readme = ""Hi! Script is Running! "" + counter + ""\n"";
          }
      
      
      }
      ";
          
          private string readme = "";            // Displayed on the GUI
          private string compilerErrorMessages = "";        // Displayed on the GUI
      
          void OnGUI() 
          {
              // ********** Display the script in Unity
              scriptText = GUI.TextArea(new Rect(10, 10, 700, 500), scriptText);
              
              // ********** Compile your script
              if (GUI.Button(new Rect(720, 10, 300, 30), "Compile and Run"))
              {                            
                  Compile ();      // Compile the script. Write errors to "compilerErrorMessages", if any.
              }
              
              // ********** Display any compiler errors
              GUI.TextArea(new Rect(10, 510, 700, 50), compilerErrorMessages);  // The console for displaying errors.
              
              // ********** Display the Script's Output.
              GUI.TextArea (new Rect(720, 50, 300, 30), readme);     
          }
          
          private Assembly generatedAssembly;                    // Compiled code is called an "Assembly"
          private Type myScript_Type = null;                    // These two variables are used run the compiled code.
          private object myScript_Instance = null;            // These two variables are used run the compiled code.
          
          private void Compile()
          {
              try
              {
                  compilerErrorMessages = "";  // clear any previous messages
                  
                  // ********** Create an instance of the C# compiler   
                  CSharpCodeProvider codeProvider = new CSharpCodeProvider();
                  
                  // ********** add compiler parameters
                  CompilerParameters compilerParams = new CompilerParameters();
                  compilerParams.CompilerOptions = "/target:library /optimize /warn:0"; 
                  compilerParams.GenerateExecutable = false;
                  compilerParams.GenerateInMemory = true;
                  compilerParams.IncludeDebugInformation = false;
                  compilerParams.ReferencedAssemblies.Add("System.dll");
                  compilerParams.ReferencedAssemblies.Add("System.Core.dll");
                  
                  // ********** actually compile the code  ??????? THIS LINE WORKS IN UNITY EDITOR --- BUT NOT IN BUILD ??????????
                  CompilerResults results = codeProvider.CompileAssemblyFromSource(compilerParams,scriptText);
                  
                  // ********** Do we have any compiler errors
                  if (results.Errors.Count > 0)
                  {
                      foreach (CompilerError error in results.Errors)
                          compilerErrorMessages = compilerErrorMessages + error.ErrorText + '\n';
                  }
                  else
                  {
                      // ********** get a hold of the actual assembly that was generated
                      generatedAssembly = results.CompiledAssembly;
                          
                      if(generatedAssembly != null)
                      {
                          // get type of class Calculator from just loaded assembly
                          myScript_Type = generatedAssembly.GetType("MyScript");
                          
                          // create instance of class MyScript
                          myScript_Instance = Activator.CreateInstance(myScript_Type);
                          
                          // Say success!
                          compilerErrorMessages = "Success!";
                      }
                  }
              }
              catch(Exception o)
              {
                  compilerErrorMessages = ""+o.Message +"\n"+ o.Source +"\n"+ o.StackTrace +"\n";
              }
              
          }
          
      }