WCF Interface as parameter

Question

I am using interface as input parameter in OperationContract. But when i generate proxy class at client side. I am not able to access the members of interface or class implemeting the ITransaction interface. I am only geeting is object

1. Service Interface

   [ServiceContract]
   public interface IServiceInterface
   {
   [OperationContract]
   string SyncDatabase(ITransaction TransactionObject);
   }
   

2. Service class

   class SyncService:IServiceInterface
   {
   
       public string SyncDatabase(ITransaction TransactionObject)
       {
       return "Hello There!!";    
       }
   }
   

3. Interface

   public interface ITransaction
   {
       ExpenseData ExpData { get; set; }
       void Add(ITransaction transactionObject);
   }
   

4. Data Contract

   [DataContract]
   public class Transaction:ITransaction
   {
       [DataMember]
       public ExpenseData ExpData
       {
           get;
           set;
       }
   
       public void Add(ITransaction transactionObject)
       {
   
       }
   
    }
   

In above case should i also copy the iTransaction class and interface on client

Answer 1

You actually need to make your ServiceContract aware of the implementation of the interface you pass as a parameter, so WCF will include it in the WSDL.

This should work:

[ServiceContract]
[ServiceKnownType(typeof(Transaction))]
public interface IServiceInterface
{
     [OperationContract]
     string SyncDatabase(ITransaction TransactionObject);
}

Answer 2

Use [KnownType(typeof(testClass))].

Refer these links:

• msdn.microsoft.com/en-us/library/ms730167.aspx
• www.codeproject.com/Tips/108807/Implementing-KnownType-Attribute

Answer 3

Try making your interface the [DataContract] and use the [KnownType] attribute to tell WCF what the known implementations of that interface are.

[DataContract]
[KnownType(typeof(Transaction))]
public interface ITransaction
{
    [DataMember]
    ExpenseData ExpData { get; set; }
    void Add(ITransaction transactionObject);
}