这是书中的代码CLR via C# 3e (Microsoft) 但它在运行时出错
TypeLoadException was unhandled Could not load type 'MarshalByRefType' from assembly 'CLRviaCSharp, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'.
除“Main”方法外，所有代码均来自上述书籍。
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using System.Reflection;
using System.Runtime.Remoting;
namespace CLRviaCSharp
{
class Program
{
static void Main(string[] args)
{
Marshalling();
}
private static void Marshalling()
{
// Get a reference to the AppDomain that that calling thread is executing in
AppDomain adCallingThreadDomain = Thread.GetDomain();
// Every AppDomain is assigned a friendly string name (helpful for debugging)
// Get this AppDomain’s friendly string name and display it
String callingDomainName = adCallingThreadDomain.FriendlyName;
Console.WriteLine("Default AppDomain’s friendly name={0}", callingDomainName);
// Get & display the assembly in our AppDomain that contains the ‘Main’ method
String exeAssembly = Assembly.GetEntryAssembly().FullName;
Console.WriteLine("Main assembly={0}", exeAssembly);
// Define a local variable that can refer to an AppDomain
AppDomain ad2 = null;
// *** DEMO 1: Cross-AppDomain Communication using Marshal-by-Reference ***
Console.WriteLine("{0}Demo #1", Environment.NewLine);
// Create new AppDomain (security & configuration match current AppDomain)
ad2 = AppDomain.CreateDomain("AD #2", null, null);
MarshalByRefType mbrt = null;
// Load our assembly into the new AppDomain, construct an object, marshal
// it back to our AD (we really get a reference to a proxy)
mbrt = (MarshalByRefType)
ad2.CreateInstanceAndUnwrap(exeAssembly, "MarshalByRefType");
Console.WriteLine("Type={0}", mbrt.GetType()); // The CLR lies about the type
// Prove that we got a reference to a proxy object
Console.WriteLine("Is proxy={0}", RemotingServices.IsTransparentProxy(mbrt));
// This looks like we’re calling a method on MarshalByRefType but, we’re not.
// We’re calling a method on the proxy type. The proxy transitions the thread
// to the AppDomain owning the object and calls this method on the real object.
mbrt.SomeMethod();
// Unload the new AppDomain
AppDomain.Unload(ad2);
// mbrt refers to a valid proxy object; the proxy object refers to an invalid AppDomain
try
{
// We’re calling a method on the proxy type. The AD is invalid, exception is thrown
mbrt.SomeMethod();
Console.WriteLine("Successful call.");
}
catch (AppDomainUnloadedException)
{
Console.WriteLine("Failed call.");
}
// *** DEMO 2: Cross-AppDomain Communication using Marshal-by-Value ***
Console.WriteLine("{0}Demo #2", Environment.NewLine);
// Create new AppDomain (security & configuration match current AppDomain)
ad2 = AppDomain.CreateDomain("AD #2", null, null);
// Load our assembly into the new AppDomain, construct an object, marshal
// it back to our AD (we really get a reference to a proxy)
mbrt = (MarshalByRefType)
ad2.CreateInstanceAndUnwrap(exeAssembly, "MarshalByRefType");
// The object’s method returns a COPY of the returned object;
// the object is marshaled by value (not be reference).
MarshalByValType mbvt = mbrt.MethodWithReturn();
// Prove that we did NOT get a reference to a proxy object
Console.WriteLine("Is proxy={0}", RemotingServices.IsTransparentProxy(mbvt));
// This looks like we’re calling a method on MarshalByValType and we are.
Console.WriteLine("Returned object created " + mbvt.ToString());
// Unload the new AppDomain
AppDomain.Unload(ad2);
// mbvt refers to valid object; unloading the AppDomain has no impact.
try
{
// We’re calling a method on an object; no exception is thrown
Console.WriteLine("Returned object created " + mbvt.ToString());
Console.WriteLine("Successful call.");
}
catch (AppDomainUnloadedException)
{
Console.WriteLine("Failed call.");
}
// DEMO 3: Cross-AppDomain Communication using non-marshalable type ***
Console.WriteLine("{0}Demo #3", Environment.NewLine);
// Create new AppDomain (security & configuration match current AppDomain)
ad2 = AppDomain.CreateDomain("AD #2", null, null);
// Load our assembly into the new AppDomain, construct an object, marshal
// it back to our AD (we really get a reference to a proxy)
mbrt = (MarshalByRefType)
ad2.CreateInstanceAndUnwrap(exeAssembly, "MarshalByRefType");
// The object’s method returns an non-marshalable object; exception
NonMarshalableType nmt = mbrt.MethodArgAndReturn(callingDomainName);
// We won’t get here...
}
}
// Instances can be marshaled-by-reference across AppDomain boundaries
public sealed class MarshalByRefType : MarshalByRefObject
{
public MarshalByRefType()
{
Console.WriteLine("{0} ctor running in {1}",
this.GetType().ToString(), Thread.GetDomain().FriendlyName);
}
public void SomeMethod()
{
Console.WriteLine("Executing in " + Thread.GetDomain().FriendlyName);
}
public MarshalByValType MethodWithReturn()
{
Console.WriteLine("Executing in " + Thread.GetDomain().FriendlyName);
MarshalByValType t = new MarshalByValType();
return t;
}
public NonMarshalableType MethodArgAndReturn(String callingDomainName)
{
// NOTE: callingDomainName is [Serializable]
Console.WriteLine("Calling from ‘{0}’ to ‘{1}’.",
callingDomainName, Thread.GetDomain().FriendlyName);
NonMarshalableType t = new NonMarshalableType();
return t;
}
}
// Instances can be marshaled-by-value across AppDomain boundaries
[Serializable]
public sealed class MarshalByValType : Object
{
private DateTime m_creationTime = DateTime.Now; // NOTE: DateTime is [Serializable]
public MarshalByValType()
{
Console.WriteLine("{0} ctor running in {1}, Created on {2:D}",
this.GetType().ToString(),
Thread.GetDomain().FriendlyName,
m_creationTime);
}
public override String ToString()
{
return m_creationTime.ToLongDateString();
}
}
// Instances cannot be marshaled across AppDomain boundaries
// [Serializable]
public sealed class NonMarshalableType : Object
{
public NonMarshalableType()
{
Console.WriteLine("Executing in " + Thread.GetDomain().FriendlyName);
}
}
}
请您参考如下方法:
当您使用AppDomain.CreateInstanceAndUnwrap方法时，您应该将类型的全名传递给typeName参数。 所以，替换
ad2.CreateInstanceAndUnwrap(exeAssembly, "MarshalByRefType");
与
ad2.CreateInstanceAndUnwrap(exeAssembly, typeof(MarshalByRefType).FullName);
