Ajax - SQL Reporting Services

Question

I have a simple report in SSRS 2008 R2 that I've modified to allow the user to directly enter comments into textboxes. When the user exits the textbox I use jQuery AJAX to save the user's comments to the database via a webmethod in another aspx page.

Using POST I get the error: "HttpException (0x80004005): The HTTP verb POST used to access path '/Reports_SQL2008R2/Pages/test.aspx/SaveComments' is not allowed."

Using GET I get the error: "HTTP 404. The resource you are looking for (or one of its dependencies) could have been removed, had its name changed, or is temporarily unavailable"

Web.config (Reporting Services/ReportManager/Web.config)

<system.web>
    <webServices>   
        <protocols>
            <add name="HttpPost"/>
            <add name="HttpGet"/>
        </protocols>      
    </webServices>
</system.web>

ReportingServices.js (Reporting Services/ReportManager/ReportingServices.js - append to end of script)

function addScript(scriptFile) 
{ 
    var head = document.getElementsByTagName('head')[0]; 
    var script = document.createElement('script'); 
    script.setAttribute('language', 'JScript'); 
    script.setAttribute('type', 'text/javascript'); 
    script.setAttribute('src', scriptFile); 
    head.appendChild(script); 
} 

addScript('//ajax.googleapis.com/ajax/libs/jquery/1.11.2/jquery.min.js'); 

function pageLoad() {    
    // Fix for report not rendering in Chrome/Safari:
    // see: http://stackoverflow.com/questions/5428017/cannot-view-ssrs-2008-r2-ssrs-2012-reports-in-safari-chrome-but-works-fine-in
    var element = document.getElementById("ctl31_ctl10"); // might also have been "ctl31_ctl09"
    if (element) {
        element.style.overflow = "visible"; 
    } 

    // Test ajax
    if (typeof jQuery != 'undefined') {
        $.ajax({
            type: "POST",
            url: "test.aspx/SaveComments",
            data: '{}',
            contentType: "application/json; charset=utf-8",
            dataType: "json",
            success: function (data, textStatus, jqXHR) {
                alert("Success");
            },
            error: function (jqXHR, textStatus, errorThrown) {
                alert(errorThrown);
            }
        });
    }
}

Test.aspx (Reporting Services/ReportManager/Pages/Test.aspx)

<%@ Page language="C#" CodeFile="Test.aspx.cs" AutoEventWireup="true" Inherits="Examples.Test" %>

Test.aspx.cs (Reporting Services/ReportManager/Pages/Test.aspx)

using System;
using System.Web;
using System.Web.Services;
using System.Web.Services.Protocols;

namespace Examples
{
    public partial class Test : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {

        }

        [WebMethod]
        public static string SaveComments(string test)
        {
            return "YES!";
        }
    }
}

[Edit]

I was unable to solve this problem. I had hoped to simply add a web method to the Reporting Services website but I can't figure out these permissions problems. My workaround has been to create a web service, but this is a bit messier because I now have to do a cross domain request:

WebService2.asmx

<%@ WebService Language="C#" Class="WebService2" %>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Services;
using System.Web.Script.Services;
using System.Web.Script.Serialization;
using System.Text;

[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
[System.ComponentModel.ToolboxItem(false)]
[System.Web.Script.Services.ScriptService]
public class WebService2 : System.Web.Services.WebService
{
    [WebMethod]
    [ScriptMethod(UseHttpGet = true, ResponseFormat = ResponseFormat.Json)]
    public string HelloWorld(string commentKey, string commentValue, string callback)
    {
        StringBuilder sb = new StringBuilder();
        JavaScriptSerializer js = new JavaScriptSerializer();
        sb.Append(callback + "(");
        sb.Append(js.Serialize(new{commentKey = commentKey, commentValue = commentValue}));
        sb.Append(");"); 

        Context.Response.Clear();
        Context.Response.ContentType = "application/json";
        Context.Response.Write(sb.ToString());
        Context.Response.End();

        return "Hello World two";
    }
}

ReportingServices.js (partial)

$.ajax({
    type: "POST",
    url: "http://localhost/WebApplication3/WebService2.asmx/HelloWorld?commentKey=KEY&commentValue=VALUE",
    contentType: "application/javascript",
    dataType: "jsonp",
    success: function (data, textStatus, jqXHR) {
        $this.each(switchToSpan);
    },
    error: function (jqXHR, textStatus, errorThrown) {
        alert(errorThrown);
        $(this).focus();
    }
});