.NET Reference Guide

A Remoting Demonstration

Last updated Jul 8, 2005.

Although the Remoting Basics topic explains what .NET Remoting is and provides necessary information, some things are best explained by demonstration. In this section you will see how to build a simple distributed application using .NET Remoting. The application consists of three parts: the types (classes) that will be remoted, the server code that hosts the remote objects, and the client code that accesses the objects.

The remote type is called ServiceClass, a very simple class that we will implement in a separate DLL called remote.dll. This class exposes a GetServerTime method that returns the current server time in a DateTime structure. It also uses a simple object id counter so that clients can call the ToString method to obtain the object's unique instance name. Clients can subscribe to the public ServiceEvent event and be notified whenever another client calls GetServerTime.

The server is the simplest of the three parts. It registers the HTTP channel and the remote type, and then sits idle waiting for client connection requests. When a connection request arrives, the remoting infrastructure creates a ServiceClass object instance if required, and hooks up the communication between the client and the object.

The client also must register a communications channel, and also the remote type that it will be using. It then subscribes to the ServiceEvent event and calls GetServerTime to obtain the current server time. After displaying the time, the client waits for the user to exit the program. While it's waiting, the client handles any incoming events. Upon exit, it unsubscribes from the event.

This is a very simple application, but it illustrates some key Remoting concepts.