Why can't I access my WCF web service with Javascript?

Question

I\'m new at AJAX and I\'m trying to access a WCF web service the following way:

$(function () {
    $(\'#formNew\').submit(function () {
        var datos =          


        

Answer 1

I normally use the following configuration to enable ajax calls to my WCF services:

1) First I create a JSON endpoint behaviour in Web.config and associate my service to it:

<system.serviceModel>
  <behaviors>
    <endpointBehaviors>
      <behavior name="WebHttpJson">
        <webHttp defaultBodyStyle="Wrapped"
                 defaultOutgoingResponseFormat="Json" />
      </behavior>
    </endpointBehaviors>
  </behaviors>
  <services>
    <service name="MyApp.LoginService">
      <endpoint address=""
                behaviorConfiguration="WebHttpJson"
                binding="webHttpBinding"
                contract="MyApp.LoginService" />
    </service>
  </services>
</system.serviceModel>

2) Then I can simply define my WCF service like this:

[ServiceContract]
public class LoginService
{
    [OperationContract]
    public void SignIn(string email, string pswd)
    {
        // Check credentials and create session cookie
    }
}

3) And finally make jQuery ajax calls like showed below:

$.ajax({
    contentType: 'application/json; charset=utf-8',
    url: serviceUrl + '/SignIn',
    type: 'POST',
    data: JSON.stringify({
        email: 'john.doe@abc.com', 
        pswd: 'qwerty'
    }),
    success: function () { alert('success!'); },
    error: function () { alert('error!'); }
});

Answer 2

The JSON.stringify(data) use is to convert a javascript object to json representation.

I think that in the success\error functions you need to go the other way:

 success: function (data) {
                            alert("Exito " + JSON.parse(data));
                          },
 error:   function (data) {
                            alert("Error " + JSON.parse(data));
                          }

(when using JSON.parse, JSON.stringify - make sure you included the json2.min.js in your project)