詳解.NET中的動態編譯技術

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Reflection;

namespace RemoteAccess

{

    ///

          /// Interface that can be run over the remote AppDomain boundary.

          ///

          public interface IRemoteInterface

          {

                   object Invoke(string lcMethod,object[] Parameters);

          }

          ///

          /// Factory class to create objects exposing IRemoteInterface

          ///

          public class RemoteLoaderFactory : MarshalByRefObject

          {

                   private const BindingFlags bfi = BindingFlags.        Instance | BindingFlags.Public           | BindingFlags.CreateInstance;

                   public RemoteLoaderFactory() {}

        public IRemoteInterface Create( string assemblyFile, string typeName,         object[] constructArgs )

                   {

                 return (IRemoteInterface) Activator.CreateInstanceFrom(

                 assemblyFile, typeName, false, bfi, null, constructArgs,

                                   null, null, null ).Unwrap();

                   }

          }       

}

//get the code to compile

string strSourceCode = this.txtSource.Text;

//1. Create an addtional AppDomain

AppDomainSetup bjSetup = new AppDomainSetup();

objSetup.ApplicationBase = AppDomain.CurrentDomain.BaseDirectory;

AppDomain bjAppDomain = AppDomain.CreateDomain("MyAppDomain", null, objSetup);

// 1.Create a new CSharpCodePrivoder instance

CSharpCodeProvider bjCSharpCodePrivoder = new CSharpCodeProvider();

// 2.Sets the runtime compiling parameters by crating a new CompilerParameters instance

CompilerParameters bjCompilerParameters = new CompilerParameters();

objCompilerParameters.ReferencedAssemblies.Add("System.dll");

objCompilerParameters.ReferencedAssemblies.Add("System.Windows.Forms.dll");

// Load the remote loader interface

objCompilerParameters.ReferencedAssemblies.Add("RemoteAccess.dll");

// Load the resulting assembly into memory

objCompilerParameters.GenerateInMemory = false;

objCompilerParameters.OutputAssembly = "DynamicalCode.dll";

// 3.CompilerResults: Complile the code snippet by calling a method from the provider

CompilerResults cr = objCSharpCodePrivoder.CompileAssemblyFromSource(objCompilerParameters, strSourceCode);

if (cr.Errors.HasErrors)

{

    string strErrorMsg = cr.Errors.Count.ToString() + " Errors:";

    for (int x = 0; x < cr.Errors.Count; x++)

    {

        strErrorMsg = strErrorMsg + "\r\nLine: " +

                     cr.Errors[x].Line.ToString() + " - " +

                     cr.Errors[x].ErrorText;

    }

    this.txtResult.Text = strErrorMsg;

    MessageBox.Show("There were build erros,    please modify your code.", "Compiling Error");

    return;

}

// 4. Invoke the method by using Reflection

RemoteLoaderFactory factory = (RemoteLoaderFactory)objAppDomain.CreateInstance("RemoteAccess","RemoteAccess.RemoteLoaderFactory").Unwrap();

// with help of factory, create a real 'LiveClass' instance

object bjObject = factory.Create("DynamicalCode.dll", "Dynamicly.HelloWorld", null);

if (objObject == null)

{

    this.txtResult.Text = "Error: " + "Couldn't load class.";

    return;

}

// *** Cast object to remote interface, avoid loading type info

IRemoteInterface bjRemote = (IRemoteInterface)objObject;

object[] bjCodeParms = new object[1];

objCodeParms[0] = "Allan.";

string strResult = (string)objRemote.Invoke("GetTime", objCodeParms);

this.txtResult.Text = strResult;

//Dispose the objects and unload the generated DLLs.

objRemote = null;

AppDomain.Unload(objAppDomain);

System.IO.File.Delete("DynamicalCode.dll");

對於客戶端的輸入程式，我們需要繼承於MarshalByRefObject類和IRemoteInterface介面，並新增對RemoteAccess程式集的引用。以下為輸入：

using System;

using System.Reflection;

using RemoteAccess;

namespace Dynamicly

{

    public class HelloWorld : MarshalByRefObject,IRemoteInterface

    {

        public object Invoke(string strMethod,object[] Parameters)

        {

            return this.GetType().InvokeMember(strMethod, BindingFlags.      InvokeMethod,null,this,Parameters);

        }

        public string GetTime(string strName)

        {

            return  "Welcome " + strName + ", Check in at " + System.DateTime.Now.ToString();

        }

    }

}