How to return Faults in JSON from AJAX Enabled WCF Service?

Question

I have an AJAX-enabled WCF service (with enableWebScript in the behavior) that has a ValidationFault which I created.

Here's the service:

[ServiceContract]
public interface ICoreWCF
{
    /// <summary>
    /// Saves the Customer.
    /// </summary>
    [OperationContract]
    [WebInvoke(BodyStyle = WebMessageBodyStyle.WrappedRequest)]
    [FaultContract(typeof(ValidationFault))]
    void Customer_Save(Customer customer);
}

Here's the fault:

[DataContract]
public class ValidationFault
{
    [DataMember(Name = "success")]
    public bool Success { get; set; }

    [DataMember(Name = "msg")]
    public string ValidationMessage { get; set; }

    [DataMember(Name = "errors")]
    public Dictionary<string, string> Errors { get; set; }
}

I would like to send this fault back to the client javascript. The problem is that my custom fault's DataMembers are ignored and a general exception is returned.

How can I send the errors collection to the client?

I already tried writing my own IErrorHandler similar to this, such that it uses Exception Handling Application Block to convert an exception to a fault, and then the IErrorHandler serializes the resulting fault. But it appears that the JsonErrorHandler of the WebScriptingEnablingBehavior is not dealing well with the resulting Message object.

Thanks.

Take a look [here][1] its been answered already. [1]: http://stackoverflow.com/questions/1272877/returning-error-details-from-ajax-enabled-wcf-service — Bryan Corazza, Jul 24 '11 at 16:49
Thanks @Bryan. I saw this question, but unfortunately I am experiencing the same problem as described by this answer: http://stackoverflow.com/questions/1272877/returning-error-details-from-ajax-enabled-wcf-service/3705135#3705135 — Dor Rotman, Jul 26 '11 at 07:21

score 0 · Answer 1 · edited Dec 14 '13 at 09:35

0

in webinvoke you can add RequestFormat=WebMessageFormat.Json, ResponseFormat=WebMessageFormat.Json try it

edited Dec 14 '13 at 09:35

Ria

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answered Jul 25 '11 at 01:54

yapingchen

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score 0 · Answer 2 · answered Aug 04 '11 at 10:27

If you have implemented IErrorHandler and associated it to service using using custom behavior inherited from WebHttpBehavior as sighted by link then perhaps you should try adding default request/response format etc. For example,

private class CustomWebScriptBehavior : WebHttpBehavior
{
    protected override void AddServerErrorHandlers(ServiceEndpoint endpoint,
        System.ServiceModel.Dispatcher.EndpointDispatcher endpointDispatcher)
    {
        // clear current error handlers
        endpointDispatcher.ChannelDispatcher.ErrorHandlers.Clear();
        // add our error handler
        endpointDispatcher.ChannelDispatcher.ErrorHandlers.Add(
                new ErrorHandler(true));
    }

    private WebMessageFormat _requestFormat;
    private WebMessageFormat _responseFormat;

    public CustomWebScriptBehavior()
    {
        _requestFormat = _responseFormat = WebMessageFormat.Json;
    }

    public override bool AutomaticFormatSelectionEnabled
    {
        get { return false; }
        set { throw new NotSupportedException(); }
    }

    public override WebMessageBodyStyle DefaultBodyStyle
    {
        get { return WebMessageBodyStyle.WrappedRequest; }
        set { throw new NotSupportedException(); }
    }

    public override WebMessageFormat DefaultOutgoingRequestFormat
    {
        get { return _requestFormat; } 
        set { _requestFormat = value; }
    }

    public override WebMessageFormat DefaultOutgoingResponseFormat
    {
        get { return _responseFormat; }
        set { _responseFormat = value; }
    }
}

This will eliminate the need to specify WebInvoke attribute for each method.

Thanks for the answer, VinayC, but unfortunately that doesn't solve my problem. — Dor Rotman, Aug 07 '11 at 07:50

How to return Faults in JSON from AJAX Enabled WCF Service?

2 Answers2