AuthenticationProxy.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Runtime.Remoting.Proxies;
using System.Runtime.Remoting.Messaging;
using System.Reflection;
using System.Threading;
namespace ProxyWithAOP
{
public class AuthenticationProxy<T> : RealProxy
{
private readonly T _decorated;
public AuthenticationProxy(T decorated)
: base(typeof(T))
{
_decorated = decorated;
}
private void Log(string msg, object arg = null)
{
Console.ForegroundColor = ConsoleColor.Green;
Console.WriteLine(msg, arg);
Console.ResetColor();
}
public override IMessage Invoke(IMessage msg)
{
var methodCall = msg as IMethodCallMessage;
var methodInfo = methodCall.MethodBase as MethodInfo;
if (Thread.CurrentPrincipal.IsInRole("ADMIN"))
{
try
{
Log("User authenticated - You can execute '{0}' ", methodCall.MethodName);
var result = methodInfo.Invoke(_decorated, methodCall.InArgs);
return new ReturnMessage(result, null, 0, methodCall.LogicalCallContext, methodCall);
}
catch (Exception e)
{
Log(string.Format("User authenticated - Exception {0} executing '{1}'", e), methodCall.MethodName);
return new ReturnMessage(e, methodCall);
}
}
Log("User not authenticated - You can't execute '{0}' ", methodCall.MethodName);
return new ReturnMessage(-1, null, 0, methodCall.LogicalCallContext, methodCall);
}
}
}
DynamicProxy.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.Remoting.Proxies;
using System.Runtime.Remoting.Messaging;
using System.Reflection;
using System.Text;
using System.Threading.Tasks;
namespace ProxyWithAOP
{
class DynamicProxy<T> : RealProxy
{
private readonly T _decorated;
public DynamicProxy(T decorated)
: base(typeof(T))
{
_decorated = decorated;
}
private void Log(string msg, object arg = null)
{
Console.ForegroundColor = ConsoleColor.Red;
Console.WriteLine(msg, arg);
Console.ResetColor();
}
public override IMessage Invoke(IMessage msg)
{
var methodCall = msg as IMethodCallMessage;
var methodInfo = methodCall.MethodBase as MethodInfo;
Log("In Dynamic Proxy - Before executing '{0}'", methodCall.MethodName);
try
{
var result = methodInfo.Invoke(_decorated, methodCall.InArgs);
Log("In Dynamic Proxy - After executing '{0}' ", methodCall.MethodName);
return new ReturnMessage(result, null, 0, methodCall.LogicalCallContext, methodCall);
}
catch (Exception e)
{
Log(string.Format("In Dynamic Proxy- Exception {0} executing '{1}'", e), methodCall.MethodName);
return new ReturnMessage(e, methodCall);
}
}
}
}
我已将两种方法声明为 - int GetCustomer(T entity);
和double GetBalance(T entity);
在管道中添加方法
var decorated = TraceProxy<ICustomerOperations>.Create(new CustomerOperations());
decorated = AuthenticationProxy<ICustomerOperations>.Create(decorated);
现在我使用装饰器调用我的客户方法
decorated.GetCustomer(1);
decorated.GetBalance(1);
上面的方法有不同的返回类型,如int和string
当用户未在AuthenticationProxy类中进行身份验证时,它将对象返回为return new ReturnMessage(-1, null, 0, methodCall.LogicalCallContext, methodCall);
(Authentication.cs调用方法)
decorated.GetCustomer(1);
调用已成功,因为返回类型匹配为int
。但是,decorated.GetBalance(1);
会将InvalidCastException
异常作为其超出double
返回类型的值。{/ p>
那么如何解决这个问题呢?我想让它变得通用,以便不存在返回类型问题。