Issue with implementing multiple service in wcf

Question

Hi i have a issue with implementing multiple service in wcf.. i hv following code [ServiceContract] public interface IMultipleService { [OperationContract] string DoWork(); } [ServiceContract] public interface IMultiplePublicService { [OperationContract] string DoPublicWork(); } [ServiceContract] public interface IMultipleConfidentialService { [OperationContract] string DoConfidentialWork(); } // Service implementation public class MultipleService : IMultipleServiceIMultiplePublicServiceIMultipleConfidentialService { public string DoWork() { return Method1 : DoWork called !!; } public string DoPublicWork() { return Method2: DoPublicWork called !!; } public string DoConfidentialWork() { return Method3: DoConfidentialWork called !!; } } If i write [ServiceBehaviorAttribute(InstanceContextMode = InstanceContextMode.PerCall)] so all service contract implement PerCall session mode. I want to impliment IMultipleService as PerCall sessionmode IMultiplePublicService as PerSession and IMultipleConfidentialService as Single.. Please help..?

Ramesh Maruthi · Answer

Hi Pramod First you need to be clear what a service is. Do you mean a single endpoint or multiple endpoints in the same host? Assuming you mean a single endpoint then yes but with a little work. An endpoint can only implement a single interface; so what you need to do is combine all the interfaces you want to implement into a single interface public interface IMyInterface : IInterface1 IInterface2 and then implement them all inside your implementation class. What you cannot do is have multiple interfaces and multiple implementations magically merge into a single endpoint. Other solution: I would suggest you separate the interfaces and do not make your ServiceContract interface inherit other interface types. So for WCF services you will define the following types: IMyService interface for ServiceContract MyService class for implementing the IMyService ServiceContract Then you might have other interface types like IMyInterface1 IMyInterface2 etc.... Since these interfaces are not WCF specific you should not make them the base type of your ServiceContract interfaces. You can let your MyService class implement these interfaces directly. In addition for reusing purpose you can also consider the composite pattern when incorporating those helper interfaces into your service code. For example instead of implementing the IMyInteface1 IMyInterface2 directly on your MyService class you can define another class called MyHelperClass which has the following definition: public class MyHelperClass: IMyInterface1 IMyInterface2 .... { } And in your WCF service you can use the MyHelperClass as a member variable so as to incorporating the interfaces implemented by MyHelperClass. e.g. public class MyService: IMyservice{ MyHelperClass __helper = new MyHelperClass(); .... } for more info see this links http://www.ecanarys.com/blog-entry/how-implement-multiple-service-contract-single-wcf-service http://debugmode.net/2010/05/26/multiplecontracts/ http://dotnetmentors.com/multiple-wcf-services-in-one-solution-with-multiple-endpoints-and-hosting.aspx