I have seen so many questions on SO about this, but I can't find what is missing in my code.

I'm implementing CORS cause I don't want to use JSONP.

I know this is a preflighted request and I think I'm adding the correct headers.

The error is that the website doesn't seem to like my WCF and every time I do a request, an OPTION method called is made even tho I have the Access-Control-Allow-Methods header.

I just want to make a POST call to my WCF with a contentType: application/json,

The WCF is self hosted, the web application is on IIS 7.5.

What Chrome shows:

What fiddler shows

Contract

<OperationContract()>

<WebInvoke(Method:=POST,

           RequestFormat:=WebMessageFormat.Json,

           ResponseFormat:=WebMessageFormat.Json,

           BodyStyle:=WebMessageBodyStyle.WrappedRequest)>

<FaultContract(GetType(ServiceFault))>

Function LookUpPerson(person As Person) _

                     As List(Of Person)

app.config

<serviceHostingEnvironment multipleSiteBindingsEnabled=true aspNetCompatibilityEnabled=true />

<bindings>

  <webHttpBinding>

    <binding name=webHttpBindingWithJsonP

             crossDomainScriptAccessEnabled=true>

      <security mode=None />

    </binding>

  </webHttpBinding>

</bindings>



<services>

  <service name=Project.Services.Person>  

    <endpoint address=ws  binding=wsHttpBinding     contract=Project.Services.Interfaces.IPublic />   

    <endpoint address=    binding=webHttpBinding    contract=Project.Services.Interfaces.IPublic

              behaviorConfiguration=jsonBehavior/>

    <host>

      <baseAddresses>

        <add baseAddress=http://localhost:8732/ />

      </baseAddresses>

    </host>

  </service>

</services>



<extensions>

  <behaviorExtensions>

    <add name=customHeaders

         type=Project.Services.Utilities.EnableCrossOriginResourceSharingBehavior, Project.Services, Version=1.0.0.0, Culture=neutral/>

  </behaviorExtensions>

</extensions>



<endpointBehaviors>

  <behavior name=jsonBehavior>

    <webHttp/>

    <customHeaders />

  </behavior>

</endpointBehaviors>

javascript

$.ajax({

    url: http://192.168.0.61:8282/Project.Services.Person/LookUpPerson,

    type: POST,

    contentType: application/json,

    crossDomain: true,

    dataType: json,

    data: { person: JSON.stringify(person) },

    success: function (data) {

        // doing something

    },

    error: function (error) {

        // doing something

    }

});

On the WCF I have the following handlers, according to http://enable-cors.org/server_wcf.html

Public Class CustomHeaderMessageInspector

        Implements IDispatchMessageInspector



        Private requiredHeaders As Dictionary(Of String, String)

        Public Sub New(headers As Dictionary(Of String, String))

            requiredHeaders = If(headers, New Dictionary(Of String, String)())

        End Sub



        Public Function AfterReceiveRequest(ByRef request As System.ServiceModel.Channels.Message,

                                            channel As System.ServiceModel.IClientChannel,

                                            instanceContext As System.ServiceModel.InstanceContext) _

                                        As Object _

                                        Implements System.ServiceModel.Dispatcher.IDispatchMessageInspector.AfterReceiveRequest

            Return Nothing

        End Function



        Public Sub BeforeSendReply(ByRef reply As System.ServiceModel.Channels.Message,

                                   correlationState As Object) _

                               Implements System.ServiceModel.Dispatcher.IDispatchMessageInspector.BeforeSendReply

            Dim httpHeader = TryCast(reply.Properties(httpResponse), HttpResponseMessageProperty)

            For Each item In requiredHeaders

                httpHeader.Headers.Add(item.Key, item.Value)

            Next

        End Sub



    End Class

And

Public Class EnableCrossOriginResourceSharingBehavior

        Inherits BehaviorExtensionElement

        Implements IEndpointBehavior



        Public Sub AddBindingParameters(endpoint As ServiceEndpoint, bindingParameters As System.ServiceModel.Channels.BindingParameterCollection) _

                                        Implements System.ServiceModel.Description.IEndpointBehavior.AddBindingParameters



        End Sub



        Public Sub ApplyClientBehavior(endpoint As ServiceEndpoint, clientRuntime As System.ServiceModel.Dispatcher.ClientRuntime) _

                                         Implements System.ServiceModel.Description.IEndpointBehavior.ApplyClientBehavior



        End Sub



        Public Sub ApplyDispatchBehavior(endpoint As ServiceEndpoint, endpointDispatcher As System.ServiceModel.Dispatcher.EndpointDispatcher) _

                                        Implements System.ServiceModel.Description.IEndpointBehavior.ApplyDispatchBehavior

            Dim requiredHeaders = New Dictionary(Of String, String)()



            requiredHeaders.Add(Access-Control-Allow-Origin, *)

            requiredHeaders.Add(Access-Control-Allow-Methods, POST, GET, OPTIONS)

            requiredHeaders.Add(Access-Control-Allow-Headers, Origin, Content-Type, Accept)

            requiredHeaders.Add(Access-Control-Max-Age, 1728000)



            endpointDispatcher.DispatchRuntime.MessageInspectors.Add(New CustomHeaderMessageInspector(requiredHeaders))

        End Sub



        Public Sub Validate(endpoint As ServiceEndpoint) _

            Implements System.ServiceModel.Description.IEndpointBehavior.Validate



        End Sub



        Public Overrides ReadOnly Property BehaviorType() As Type

            Get

                Return GetType(EnableCrossOriginResourceSharingBehavior)

            End Get

        End Property



        Protected Overrides Function CreateBehavior() As Object

            Return New EnableCrossOriginResourceSharingBehavior()

        End Function



    End Class

Sorry for the long post, I wanted to be specific.

Thanks in advance.

UPDATE

If I use contentType: text/plain I get the error on the chrome console:

POST http://192.168.0.61:8282/Project.Services.Person/LookUpPerson 400 (Bad Request)