How to: Create an Instance of a Client-Activated Type
This topic is specific to a legacy technology that is retained for backward compatibility with existing applications and is not recommended for new development. Distributed applications should now be developed using the Windows Communication Foundation (WCF).
This article shows two ways of instantiating a client-activated object. The first method uses CreateInstance, the second uses the new operator.
Create and register a TcpChannel
Dim channel As TcpChannel = New TcpChannel() ChannelServices.RegisterChannel(channel, False) TcpChannel channel = new TcpChannel(); ChannelServices.RegisterChannel(channel, false);
Register the client-activated object
RemotingConfiguration.RegisterActivatedClientType( _ GetType(MyRemoteObject), _ "tcp://localhost:1234/MyServer") RemotingConfiguration.RegisterActivatedClientType( typeof(MyRemoteObject), "tcp://localhost:1234/MyServer");
Call CreateInstance
Dim url() As Object = {New UrlAttribute("tcp://localhost:1234/Server")} Dim obj As MyRemoteObject = CType(Activator.CreateInstance( _ GetType(MyRemoteObject), _ Nothing, _ url), MyRemoteObject) object[] url = { new UrlAttribute("tcp://localhost:1234/Server") }; MyRemoteObject obj = (MyRemoteObject)Activator.CreateInstance( typeof(MyRemoteObject), null, url);
Create and register a channel
Dim channel As TcpChannel = New TcpChannel() ChannelServices.RegisterChannel(channel, False) TcpChannel channel = new TcpChannel(); ChannelServices.RegisterChannel(channel, false);
Register the client-activated object
RemotingConfiguration.RegisterActivatedClientType( _ GetType(MyRemoteObject), _ "tcp://localhost:1234/MyServer") RemotingConfiguration.RegisterActivatedClientType( typeof(MyRemoteObject), "tcp://localhost:1234/MyServer");
Call the new operator
Dim obj As MyRemoteObject = New MyRemoteObject(123) MyRemoteObject obj = new MyRemoteObject(123);
The following code illustrates both methods of creating a client-activated instance:
Imports System
Imports System.Runtime.Remoting
Imports System.Runtime.Remoting.Channels
Imports System.Runtime.Remoting.Channels.Tcp
Imports System.Runtime.Remoting.Activation
Imports Server
Module Client
Sub Main()
' Create and register a channel
Dim channel As TcpChannel = New TcpChannel()
ChannelServices.RegisterChannel(channel, False)
' Register the client activated object
RemotingConfiguration.RegisterActivatedClientType( _
GetType(MyRemoteObject), _
"tcp://localhost:1234/MyServer")
' Call Activator.CreateInstance
Dim obj As MyRemoteObject = CType(Activator.CreateInstance( _
GetType(MyRemoteObject), _
Nothing, _
url), MyRemoteObject)
' OR call operator new
Dim obj As MyRemoteObject = New MyRemoteObject(123)
Console.WriteLine("Client.Main(): GetValue returned: {0}", obj.GetValue())
Console.WriteLine("Client.Main(): Calling SetValue(10)")
obj.SetValue(10)
Console.WriteLine("Client.Main(): GetValue returned: {0}", obj.GetValue())
End Sub
End Module
using System;
using System.Runtime.Remoting;
using System.Runtime.Remoting.Activation;
using System.Runtime.Remoting.Channels;
using System.Runtime.Remoting.Channels.Tcp;
using Server;
namespace Client
{
class Client
{
static void Main(string[] args)
{
// Create and register channel
TcpChannel channel = new TcpChannel();
ChannelServices.RegisterChannel(channel, false);
// Register client activated object
RemotingConfiguration.RegisterActivatedClientType(
typeof(MyRemoteObject),
"tcp://localhost:1234/MyServer");
// Call Activator.CreateInstance
object[] url = { new UrlAttribute("tcp://localhost:1234/Server") };
MyRemoteObject obj = (MyRemoteObject)Activator.CreateInstance(
typeof(MyRemoteObject),
null,
url);
// OR call operator new
MyRemoteObject obj = new MyRemoteObject(123);
Console.WriteLine("Client.Main(): GetValue returned: " + obj.GetValue());
Console.WriteLine("Client.Main(): Calling SetValue(10)");
obj.SetValue(10);
Console.WriteLine("Client.Main(): GetValue returned: " + obj.GetValue());
}
}
}
This example requires:
- References to the System and System.Runtime.Remoting namespaces, and the namespace that implements MyRemoteObject.
Activation of Remote Objects
Configuration of Remote Applications
Server Activation
Lifetime Leases
Client Activation