Enable CORS Service Behavior

    public class EnableCrossOriginResourceSharingBehavior : IEndpointBehavior, System.ServiceModel.Dispatcher.IDispatchMessageInspector
        {

            public static string AllowedMethods {get;set;}
            public static string AllowedHeaders { get; set; }

            static EnableCrossOriginResourceSharingBehavior()
            {
                EnableCrossOriginResourceSharingBehavior.AllowedHeaders = "GET,POST,OPTIONS";
                EnableCrossOriginResourceSharingBehavior.AllowedHeaders = "X-Requested-With,Content-Type,origin";
            }
            public void AddBindingParameters1(ServiceEndpoint endpoint, System.ServiceModel.Channels.BindingParameterCollection bindingParameters)
            {
            }
            void IEndpointBehavior.AddBindingParameters(ServiceEndpoint endpoint, System.ServiceModel.Channels.BindingParameterCollection bindingParameters)
            {
                AddBindingParameters1(endpoint, bindingParameters);
            }


            public void ApplyClientBehavior1(ServiceEndpoint endpoint, System.ServiceModel.Dispatcher.ClientRuntime clientRuntime)
            {
            }
            void IEndpointBehavior.ApplyClientBehavior(ServiceEndpoint endpoint, System.ServiceModel.Dispatcher.ClientRuntime clientRuntime)
            {
                ApplyClientBehavior1(endpoint, clientRuntime);
            }

            public void ApplyDispatchBehavior1(ServiceEndpoint endpoint, System.ServiceModel.Dispatcher.EndpointDispatcher endpointDispatcher)
            {
                endpointDispatcher.DispatchRuntime.MessageInspectors.Add(this);
                //          endpointDispatcher.DispatchRuntime.MessageInspectors.Add(New CustomHeaderMessageInspector(requiredHeaders))
            }
            void IEndpointBehavior.ApplyDispatchBehavior(ServiceEndpoint endpoint, System.ServiceModel.Dispatcher.EndpointDispatcher endpointDispatcher)
            {
                ApplyDispatchBehavior1(endpoint, endpointDispatcher);
            }


            public void Validate1(ServiceEndpoint endpoint)
            {
            }
            void IEndpointBehavior.Validate(ServiceEndpoint endpoint)
            {
                Validate1(endpoint);
            }

            public object AfterReceiveRequest(ref System.ServiceModel.Channels.Message request, System.ServiceModel.IClientChannel channel, System.ServiceModel.InstanceContext instanceContext)
            {
                System.ServiceModel.Channels.HttpRequestMessageProperty httpHeader = request.Properties[System.ServiceModel.Channels.HttpRequestMessageProperty.Name] as System.ServiceModel.Channels.HttpRequestMessageProperty;
                if (httpHeader != null)
                {
                    if (httpHeader.Method.ToLowerInvariant() == "options")
                    {
                        request.Properties.Add("is_options_header", httpHeader);
                    }
                }
                return null;
            }

            public void BeforeSendReply(ref System.ServiceModel.Channels.Message reply, object correlationState)
            {
                //System.Diagnostics.Debugger.Launch()
                if (reply.IsFault) return;
                var props = System.ServiceModel.OperationContext.Current.IncomingMessageProperties;
                if (props.ContainsKey("is_options_header")){
                    System.ServiceModel.Channels.HttpRequestMessageProperty httpHeader =   props["is_options_header"] as System.ServiceModel.Channels.HttpRequestMessageProperty;
                    System.ServiceModel.Channels.HttpResponseMessageProperty resProp = reply.Properties.Values.OfType<System.ServiceModel.Channels.HttpResponseMessageProperty>().FirstOrDefault();
                    //      If respo.StatusCode = Net.HttpStatusCode.MethodNotAllowed Then
                    Dictionary<string, string> requiredHeaders = new Dictionary<string, string>();
                    requiredHeaders.Add("Access-Control-Allow-Origin", "*");
                    requiredHeaders.Add("Access-Control-Request-Method", EnableCrossOriginResourceSharingBehavior.AllowedMethods );
                    requiredHeaders.Add("Access-Control-Allow-Headers", EnableCrossOriginResourceSharingBehavior.AllowedHeaders );
                    requiredHeaders.Add("Access-Control-Max-Age", TimeSpan.FromHours(1).TotalSeconds.ToString());
                    requiredHeaders.Add("X-EP-Behaviour", typeof(EnableCrossOriginResourceSharingBehavior).Name);
                    foreach (string item in requiredHeaders.Keys)
                    {
                        resProp.Headers.Add(item, requiredHeaders[item]);
                    }

                    if (resProp.StatusCode == System.Net.HttpStatusCode.MethodNotAllowed)
                    {
                        resProp.StatusCode = System.Net.HttpStatusCode.OK;
                        resProp.SuppressEntityBody = true;
                    }
                    //End If
                }

            }
        }