Explicitly calling a service constructor when hosting a WCF web service on IIS

Question

I want to host a WCF service of mine on Microsoft IIS (IIS hosting).

To do this, I created my service:

// The service
public class MyService : IMySer         


        

Answer 1

If all you need is to call a specific constructor in your service, then you only need to implement an IInstanceProvider and attach an IServiceBehavior to your service:

IInstanceProvider

public class ServiceInstanceProvider : IInstanceProvider
{
    public object GetInstance(InstanceContext instanceContext)
    {
        return this.GetInstance(instanceContext, null);
    }

    public object GetInstance(InstanceContext instanceContext, Message message)
    {
        return new MyService(...);
    }

    public void ReleaseInstance(InstanceContext instanceContext, object instance)
    {}
}

IServiceBehavior as Attribute

public class InstanceProviderBehaviorAttribute : Attribute, IServiceBehavior
{
    public void AddBindingParameters(ServiceDescription serviceDescription,
            ServiceHostBase serviceHostBase,
            Collection endpoints,
            BindingParameterCollection bindingParameters)
    {}

    public void ApplyDispatchBehavior(ServiceDescription serviceDescription,
            ServiceHostBase serviceHostBase)
    {
        foreach (ChannelDispatcher cd in serviceHostBase.ChannelDispatchers)
        {
            foreach (EndpointDispatcher ed in cd.Endpoints)
            {
                if (!ed.IsSystemEndpoint)
                {
                    ed.DispatchRuntime.InstanceProvider = new ServiceInstanceProvider();
                }
            }
        }
    }

    public void Validate(ServiceDescription serviceDescription,
            ServiceHostBase serviceHostBase)
    {}
}

MyService with the custom ServiceBehavior Attribute

[InstanceProviderBehavior]
public class MyService : IMyService {
    public MyService() { }
    public MyService(...) : this() {
        ...
    }
   ...
}

More info on this here:

• Carlos Figueira MSDN blog: WCF Extensibility – IInstanceProvider
• Carlos Figueira MSDN blog: WCF Extensibility