WCF javascript 跨域调用

Question

I am new to javascript and I have a problem that is giving me hard times.

I want to put in a page a tracking javascript. This script will call a wcf service to track client browser information, page visited and timestamp. The problem is that I get: "405 Method Not Allowed" error on javascript call. The service will be on another domain. Now I test this on localhost. The service is working fine because I can call it from a new page in browser. Did you experienced the same problem? How can I fix this?

My javascript code is:

Wcf service code:

[ServiceContract(Name = "CustomersAssistantService", Namespace = "CustomersAssistantService")]
public interface ICustomersAssistantService
{
    [OperationContract]
    [WebGet]
    string DoWork();

    [WebInvoke(Method = "POST", BodyStyle = WebMessageBodyStyle.Wrapped, ResponseFormat = WebMessageFormat.Json)]
    [OperationContract]
    string Sum(int n1, int n2);
}

[AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)]
public class CustomersAssistantService : ICustomersAssistantService
{
    public string DoWork()
    {
        return "work done";
    }

    public string Sum(int n1, int n2)
    {
        return (n1 + n2).ToString();
    }
}

Javascript call:

function CallWcf1(){
        var _I = this;
        var url = "http://localhost:58399/CustomersAssistantService.svc/customersAssistantService/";        

            var methodUrl = _I.serviceUrl + 'dowork';

             $.ajax( {
                        url: methodUrl,
                        data: '',
                        type: "GET",
                        processData: false,
                        contentType: "application/json",
                        timeout: 10000,
                        dataType: "text",  // not "json" we'll parse
                        success: 
                        function(res) 
                        {                                    
                            if (!callback) return;
                            // *** Use json library so we can fix up MS AJAX dates
                            var result = JSON2.parse(res);
                            // *** Bare message IS result
                            if (bare)
                            { callback(result); return; }
                            // *** Wrapped message contains top level object node
                            // *** strip it off
                            for(var property in result)
                            {
                                callback( result[property] );
                                break;
                            }                    
                        },
                        error:  
                        function(xhr)
                        {
                            if (!error) return;
                            if (xhr.responseText)
                            {
                                var err = JSON2.parse(xhr.responseText);
                                if (err)
                                    error(err); 
                                else    
                                    error( { Message: "Unknown server error." })
                            }
                            return;
                        }
                    });   
    }

Am I doing something wrong?

Thanks a lot, Radu D

Answer 1

You're running into the Same Origin Policy . Ajax requests are limited to talking to the same origin ; cross-domain requests will typically be denied.

Depending on your needs, there are various approaches:

• If your users will be using only quite modern browsers (so, not IE7), you could implement Cross Origin Resource Sharing on your server. This is a standard from the W3C that allows a server to open up access to its resources cross-origin, but it's only supported in modern browsers. (And on IE, it's supported, but not via the usual XMLHttpRequest object; instead, you have to use the XDomainRequest object.)
• You could implement a JSON-P interface .
• If all you want to do is send a notification to the other domain, you can just load a resource from it (an img , a script , whatever) by adding those elements with the relevant src attribute; this means, though, that you're limited to using the GET method which is supposed to be for idempotent resources.

Answer 2

As far as I know, request for WCF must use the POST method, so change to:

type: "POST", 

In the AJAX call.