My question is: Is possible to know wich contract has been called in a multiple contract service? In this, case, in the constructor.
The implementing class of the se
I think what you want to implement is a WCF Message Inspector. A MessageInspector is a "message filter" that can intercept and inspect the messages coming in or going out of the service layer infrastructure.
On the server, you would implement the IDispatchMessageInspector Interface.
Here is a pretty good example:
http://www.aspnet4you.com/wcf/index.php/2013/01/30/message-interception-auditing-and-logging-at-wcf-pipeline/