The intent of the proxy-pattern is to provide a placeholder for another object to control access to it. It introduces an additional level of indirection. There are several reasons why you would want to do this,

1. Proxy Pattern/C# Core 2
System.Reflection.DispatchProxy

2. What is the Proxy Pattern?
• The intent of the proxy-pattern is to provide a placeholder for another object to
control access to it. It introduces an additional level of indirection. There are
several reasons why you would want to do this,
• defer the full cost of its creation and initialization until we actually need to
use it.
• A remote proxy is responsible for encoding a request and its arguments and for
sending (and retrieving) the request (and the response) to the real object.
• A virtual proxy may cache additional information about the real subject so that
it can postpone the access to it.
• A protection proxy checks whether the caller has sufficient access permissions
for perform a request.
• In many cases, real world proxies are a combination of some of these basic
proxies

3. What is System.Reflection.DispatchProxy?
• Provides a class to dynamically create proxy types that implement
a specified interface and derive from a specified DispatchProxy
type. Method invocations on the generated proxyinstance are
dispatched to that DispatchProxy base type.

4. How to use Proxy Pattern in C# Core 2
• You will need the package System.Reflection.DispatchProxy
ServiceControllerA
Client Factory
ServiceControllerB
ServiceA
Configuration
Service A

5. My Service : ServiceA
public class ServiceA : IServiceA
{
public string GetName()
{
return "Michel Bruchet";
}
}

6. My two controllers : Controller A and B
public class ControllerA : IServiceA
{
public string GetName()
{
return new ServiceA().GetName();
}
}

7. My two Classes Proxy
public class ClassProxyA : System.Reflection.DispatchProxy
{
protected override object Invoke(MethodInfo targetMethod, object[] args)
{
return new ControllerA().GetName();
}
}

8. My Factory
public IServiceA GetService()
{
if (_type == "A")
return DispatchProxy.Create<IServiceA, ClassProxyA>();
else
return DispatchProxy.Create<IServiceA, ClassProxyB>();
}
}

9. My Client
static void Main(string[] args)
{
var factory = new MyClassFactory("A");
var name = factory.GetName();
Console.Write($"hello {name}");
}