[ScriptService]
[WebService(Namespace = "http://mapserv.utah.gov/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
public class UTSGID_GeoLocator : System.Web.Services.WebService

 is above my class

I'm sorry but I thought you used the above attributes...

I think your problem is that you don't have the () after the ScriptService attribute. Your webservice should look something like this:

 <%@ WebService Language="C#" Class="UTSGID_GeoLocator" %>

using System;
using System.Web;
using System.Web.Services;
using System.Web.Services.Protocols;
using System.Web.Script.Services;
using System.Web.Script.Serialization;

[WebService(Namespace = "http://mapserv.utah.gov/")]
[WebServiceBinding(ConformsTo = WsiProfiles.None)]
[ScriptService()]
public class UTSGID_GeoLocator : System.Web.Services.WebService

    [WebMethod]
    [ScriptMethod(ResponseFormat = ResponseFormat.Json)]
    public string GetHelloWorld() {
        return "Hello World";
    }
    
}

If you haven't already, I strongly suggest you install Firebug and look at the error HTML the webservice throws at you.

Cheers, Jon. 

 my bad I guess.  I wasn't using an ashx page i'm using an asmx page with a .cs file.  The code above was in the .cs file.

no no no. You should use asmx pages.. I'll create a demo project for you...
 

Check out the Professional AJAX project at Codeplex.com

 http://www.codeplex.com/AjaxPro

I use it here at work INSTEAD OF the Microsoft ASP.NET AJAX Extensions, and it's much lighter, faster, and easier to deal with.

I couldn't get it to work as well, so I did this really ugly hack.  It probably breaks somthing down the road but it works.

1        [WebMethod(false)]
2        [ScriptMethod(ResponseFormat = ResponseFormat.Json)]
3        public string GetSamples(string Sample)
4        {
5            Portfolio Portfolio = new Portfolio();
6            Context.Response.Write(Portfolio.SampleJSON(Sample));
7            Context.Response.End();
8    
9            return "";
10       }

As far as I know its not currently possible to return JSON in asp.net,  it could be an inadvertant policy issue where microsoft doesnt want people to use other products just like datatable which is not returned as webservice. But you can always convert xml to json.

However webservice can return JSON data is when its called from within ASP.NET AJAX pages using the ScriptManager - which may not be sufficent if services are ultimately going to be called from a php application etc...

 You can however implement your own IHttpHandlerFactor and IHttpHandler classes.  They can then intercept the webservice calls and check classes, which return JSON using the JavaScriptSerializer, or the generic WebServiceHandlerFactory().

the flag works out to be "application/OrYxJson" within the Context-Type property of the request.  If this property is set, JSON gets returned, otherwise you get good old SOAP.

..

 You said:

"As far as I know its not currently possible to return JSON in asp.net,  it could be an inadvertant policy issue where microsoft doesnt want people to use other products just like datatable which is not returned as webservice. But you can always convert xml to json."

I'm not sure what that means, but of course you can return JSON.  A webservice can return it natively with or without ScriptManager.  A page can return it by outputting nothing but a JSON string. 

-Greg
 

Hi Greg,

I certainly agree that a webservice can return it natively with or without Script Manager, however not that of Asp.net as I know of which is why I said it could be a policy issue. Because one of the tenets of webservice it should provide a service in any form.  

However I will be so glad to learn if there is a way to return JSON without my above suggestions of script manager, or other ones. I am here to learn.

Maybe the following post will help:
http://weblogs.asp.net/rashid/archive/2007/09/28/implement-jsonp-in-your-asp-net-application.aspx