Duplex Message
Exchange Pattern in WCF
Duplex message
exchange pattern is a way in WCF in which client and service both can send
messages to each other independently. Duplex message exchange pattern also
known as callback.
As both
client and service need to be connected to exchange messages this patter is
quite complicated and slower than other message exchange pattern.
To implement
the duplex we have to create the separate interface and we have to create
method which can be either request-reply or one way type.
Following are the
steps to implement duplex service in wcf:-
Step 1:-
Open the
visual studio->File->New->Website->WcfService
Step 2:-
Create
interface which you use to call back from service to the client:-
[ServiceContract]
public interface IDuplexCheck
{
[OperationContract(IsOneWay=true)]
void showstatus(string res);
}
Step
3:-
Create the interface for the service in which you define
your operation:-
[ServiceContract(CallbackContract=typeof(IDuplexCheck))]
public interface IService
{
//IsOneWay=False
represents the duplex communication
[OperationContract(IsOneWay=false)]
void dataupdated();
}
