解析.NET中的动态编译技术_.Net教程

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 objSetup = new AppDomainSetup();

objSetup.ApplicationBase = AppDomain.CurrentDomain.BaseDirectory;

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

// 1.Create a new CSharpCodePrivoder instance

CSharpCodeProvider objCSharpCodePrivoder = new CSharpCodeProvider();

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

CompilerParameters objCompilerParameters = 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 objObject = 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 objRemote = (IRemoteInterface)objObject;

object[] objCodeParms = 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");

对于客户端的输入程序，我们需要继承于MarshalByRefObject类和IRemoteInterface接口，并添加对RemoteAccess程序集的引用。以下为输入：

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();

}

}

}