Is it possible to compile and run C# code on-the-fly on mobile?

Questions & Answers
1

Hi, all:

What I want to do here is to make a console in game, which is common in games with some script language like Lua.

And, as Unity uses C#, I think it might not be necessary to employ another script language, and also it could save some CSharp-Lua binding work.

After some experiments with CodeDomProvider, I could run up the console in PC setting, but I cannot figure out how to make it run on Android.

From the DDMS, I get this error log:

08-28 22:32:53.490: I/Unity(29077): SystemException: Error running gmcs: Cannot find the specified file
08-28 22:32:53.490: I/Unity(29077):   at Mono.CSharp.CSharpCodeCompiler.CompileFromFileBatch (System.CodeDom.Compiler.CompilerParameters options, System.String[] fileNames) [0x00000] in <filename unknown>:0 
08-28 22:32:53.490: I/Unity(29077):   at Mono.CSharp.CSharpCodeCompiler.CompileFromSourceBatch (System.CodeDom.Compiler.CompilerParameters options, System.String[] sources) [0x00000] in <filename unknown>:0 
08-28 22:32:53.490: I/Unity(29077):   at Mono.CSharp.CSharpCodeCompiler.CompileAssemblyFromSourceBatch (System.CodeDom.Compiler.CompilerParameters options, System.String[] sources) [0x00000] in <filename unknown>:0 
08-28 22:32:53.490: I/Unity(29077):   at System.CodeDom.Compiler.CodeDomProvider.CompileAssemblyFromSource (System.CodeDom.Compiler.CompilerParameters options, System.String[] fileNames) [0x00000] in <filename unknown>:0 
08-28 22:32:53.490: I/Unity(29077):   at InputScript._CompileCode (System.String code) [0x00000] in <filename unknown>:0 
08-28 22:32:53.490: I/Unity(29077):   at InputScript.OnGUI () [0x00000] in <filename unknown>:0

It looks like the compiler gmcs is not around on Android Mono Runtime(?)

So, does that mean Mono cannot compile C# code on-the-fly on mobile? And I still have to use Lua as the script?

2

Some weird issues arise after switching from unity3.5 to unity4.1.3.
With some trial & errors, finally I found a workaround, just skip referencing Mono.Cecil & UnityEditor, and it will be okay.

I post my code(modified) below in case someone is interested.

using UnityEngine;
using System.Collections;
using System;
using Mono.CSharp;

public class CmdConsole : MonoBehaviour/*Singleton<CmdConsole>*/
{
    public KeyCode[] m_ShortcutKeys = new KeyCode[]{KeyCode.LeftAlt, KeyCode.F12}; //the keys used to open Console;
    public bool m_IsConsoleOpen = false;

    private string m_editstr = "";
    private string m_result = "";

    private int m_cmdId = 0; //used to identify cmd

	// Use this for initialization
	void Start () {
        Mono.CSharp.Evaluator.Init(new string[] { });
        foreach (System.Reflection.Assembly assembly in AppDomain.CurrentDomain.GetAssemblies())
        {
            //Dbg.Log("refer: {0}", assembly.FullName);
            if( assembly.FullName.Contains("Cecil") || assembly.FullName.Contains("UnityEditor") )
                continue;
            Mono.CSharp.Evaluator.ReferenceAssembly(assembly);
        }
        Evaluator.Run ("using UnityEngine;

" +
“using System;”
);
}

    void Update() {
        //check if the console should be opened
        if (m_IsConsoleOpen)
            return;

        bool bAllKeysDown = true;
        foreach ( KeyCode kc in m_ShortcutKeys )
        {
            if( !Input.GetKey(kc) )
            {
                bAllKeysDown = false;
                break;
            }
        }

        if( bAllKeysDown )
        {
            m_IsConsoleOpen = true;
        }
    }

    void OnGUI()
    {
        if (!m_IsConsoleOpen)
            return;

        m_editstr = GUI.TextArea(new Rect(10, 10, 400, 100), m_editstr);

        if( GUI.Button(new Rect(420, 60, 100, 40), "Execute") )
        {
            ++m_cmdId;
            bool bSuccess = Run(m_editstr);
            m_result = string.Format("{0}: {1}", m_cmdId, bSuccess ? "OK" : "Fail");
            m_editstr = ""; //clear the script
        }

        if( GUI.Button(new Rect(530, 60, 100, 40), "Close") )
        {
            m_IsConsoleOpen = false;
        }

        if (m_result.Length > 0)
        {
            GUI.TextArea(new Rect(420, 10, 200, 30), m_result);
        }
    }


	public bool Run(string cmd) {
        return Evaluator.Run(cmd);
    }

}