Is it unusual for a web service call to have an “out” parameter?

Question

Is it unusual for a web service call to have an \"out\" parameter? If so, why?

I am using C# web service and webserive consumer also will be c# app.

Answer 1

Yes, because a web service should be thought of as taking a message (request) and spitting out a result (output).

An 'out' parameter would indicate that you want to return a modified version of the original request message...which really doesn't make sense. If you need to have multiple outputs, you need to think about how to package those values in to a single response message.