Question

I have a WCF web service that I am working on and I built it and was delighted to find that I could use complex types in it. I added some and then realized that they were still not useable as those types on the client end. This is an internal web service so these types are known on both sides. Anyway, that’s not the problem, as I took the complex types out, but I think it may have left some residual issues.

When I then changed my additions to all be base types (string, date, int, etc) then added the web service to the client project, I got a “[enumtype] is already defined” error. It occurred in the reference.cs file so I opened it up. Sure enough there were duplicate enums. Plus there were a bunch of helper (serializing) functions. The duplicate enum was from code that had been in there before I picked this web service up to work on. It had not caused an issue previously.

I opened up the reference.cs for the previous (successful) service reference. It did not have the duplicates or functions and also I noticed a difference between the entries that were in there. The reference.cs that was failing to compile had this additional attribute in several places:
[System.ServiceModel.XmlSerializerFormatAttribute()]

I also see that my new failed code was using string[] and the old was using ArrayOfString. I did not intentionally change this, but must have somehow set something differently in the process.

Does anyone have a few clues?

Thanks!

Answer 1

After a lot of experimentation this is what I found out:

Our web service up to this point was using the Request / Response classes for input and output. There were required in 1.0, and were a carry over from that. I attempted to create a simple entry point that sent in a string and returned a string. This compiled ok, but:

• Although you can use regular types for input and output, if you are using Request / Response types exchanges for other entry points, then you cannot.
• Mixed method of request / response and regular types will compile, but it will not successfully import (at least into Visual Studio 2008). What ends up being created seems to be an attempt to create input and output classes for all of the functions to translate them to their complex types, along with the Request / Response types which creates duplicate entries and will not compile.
• This then also means that you cannot send in a request object and return a string (which is how I found out that this was not allowed) – this generated an error in the unit test, which started me down this path.

So if you have a request / response web service, all functions must follow that protocol.