C# 4 and .NET 4

emote objects, Clients, and servers ❘ OC199
In the example, the URI type of the remote object class used by the client and a mode are specifi ed. The
mode WellKnownObjectMode.SingleCall means that a new instance is created for every method call;
in the sample application no state is held in the remote object.
.NET Remoting allows creating stateless and stateful remote objects. In the fi rst
example, well - known single - call objects that don ’ t hold state are used. The other object
type is called client - activated. Client - activated objects hold state. Later in this chapter,
when looking at the object activation sequence, you learn more details about these
differences and how these object types can be used.
After registration of the remote object, it is necessary to keep the server running until a key is pressed:
using System;
using System.Collections.Generic;
using System.Runtime.Remoting;
using System.Runtime.Remoting.Channels;
using System.Runtime.Remoting.Channels.Tcp;
namespace Wrox.ProCSharp.Remoting
{
class Program
{
static void Main()
{
var channel = new TcpServerChannel(8086);
ChannelServices.RegisterChannel(channel, true);
RemotingConfiguration.RegisterWellKnownServiceType(
typeof(Hello), "Hi", WellKnownObjectMode.SingleCall);
Console.WriteLine("Press return to exit");
Console.ReadLine();
}
}
}
code snippet RemoteHello /HelloServer/Program.cs
a simple Client application
The client is again a C# console application: HelloClient . With this project, you also have to reference the
System.Runtime.Remoting assembly so that the TcpClientChannel class can be used. In addition, you
have to reference the RemoteHello assembly. Although the object will be created on the remote server, the
assembly is needed on the client for the proxy to read the type information during runtime.
In the client program, create a TcpClientChannel object that ’ s registered in ChannelServices .
For the TcpChannel , you can use the default constructor, so a free port is selected. Next, the Activator
class is used to return a proxy to the remote object. The proxy is of type System.Runtime.Remoting
.Proxies.__TransparentProxy . This object looks like the real object because it offers the same methods.
The transparent proxy uses the real proxy to send messages to the channel:
using System;
using System.Runtime.Remoting.Channels;
using System.Runtime.Remoting.Channels.Tcp;
namespace Wrox.ProCSharp.Remoting
{
class Program
{
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