You want a method in a remote object to perform a long task, and you don’t want to force the client to wait while the method code executes.
Create a one-way method by applying the OneWay attribute from the System.Runtime.Remoting.Messaging namespace.
With one-way methods, the client sends a request message, and the remote object responds immediately to indicate it has begun processing. This has several consequences:
The client doesn’t need to wait while the method code executes.
The method can’t return any information to the client, either through a return value or ByRef parameter.
If the method throws an unhandled exception, it won’t be propagated back to the client.
To create a one-way method, you need ...