protected override void OnLoad(EventArgs e){
        // Get references to the farm and farm WebService object
        // the SPWebService object contains the SPWebApplications
        SPFarm thisFarm = SPFarm.Local;
        SPWebService service = thisFarm.Services.GetValue(“”);

        // Prepare the XML Writer
        XmlTextWriter xmlWriter = new XmlTextWriter(Response.OutputStream, Encoding.UTF8);

        //Start the XML Document
        xmlWriter.WriteStartDocument();

        //Create a Web Applications Element
        xmlWriter.WriteStartElement(“webapplications”);

        //**********************************************
        // NOTE: From here on everything is executed in
        //       “try catch” blocks. This is done to
        //       facilitate troubelshooting in case any
        //       errors surface. The error is caught and
        //       rendered in an xml “error” element.
        //       since the pages MIME type has been
        //       changed to XML, allowing the error
        //       to surface would render the xml document
        //       unreadable in IE.
        //***********************************************
        try
        {
            //Iterate through each web application
            foreach (SPWebApplication webApp in service.WebApplications)
            {
                //Create an XML Element for each web application
                //and include the name in the “name” attribute
                xmlWriter.WriteStartElement(“webapplication”);
                xmlWriter.WriteAttributeString(“name”, webApp.DisplayName);
                try
                {
                    //Create a sites element for the site collections
                    xmlWriter.WriteStartElement(“sites”);

                    //Iterate through each site collection
                    foreach (SPSite siteCollection in webApp.Sites)
                    {

                        //Create an XML Element for each site collection
                        //and include the url in the “url” attribute
                        xmlWriter.WriteStartElement(“site”);
                        xmlWriter.WriteAttributeString(“url”, siteCollection.Url);

                        //call the recursive method to get all the sites(webs)
                        GetWebs(siteCollection.AllWebs, xmlWriter);

                        //close the site element
                        xmlWriter.WriteEndElement();

                    }
                    //close the site collection element
                    xmlWriter.WriteEndElement();

                }
                catch (Exception siteError)
                {
                    //if an error occurs write the error message to
                    //an error element
                    xmlWriter.WriteElementString(“error”, siteError.Message);
                }
                //close the web application element
                xmlWriter.WriteEndElement();
            }
        }
        catch (Exception webAppError)
        {
            //if an error occurs write the error message to
            //an error element
            xmlWriter.WriteElementString(“error”, webAppError.Message);
        }

        // close the web applications element and document
        xmlWriter.WriteEndElement();
        xmlWriter.WriteEndDocument();
        xmlWriter.Close();
    }
    //*************************************************
    // This method is used recursively to display all
    // webs in a site collection. The Web Collection
    // from the site collection is passed in along with
    // the XML writer to continue writing the XML Document
    // where the calling method left off
    public void GetWebs(SPWebCollection allWebs, XmlTextWriter xmlWriter)
    {
        //create a webs element to contain all sites(webs)
        xmlWriter.WriteStartElement(“webs”);
        try
            {
            //iterate through each site(web)
            foreach (SPWeb web in allWebs)
            {
                if (web.Permissions.DoesUserHavePermissions(SPRights.FullMask));
                {
                    //Create an XML Element for each site(web)
                    //and include attributes for the url, title,
                    //and template information
                    xmlWriter.WriteStartElement(“web”);
                    xmlWriter.WriteAttributeString(“url”,web.Url);
                    xmlWriter.WriteAttributeString(“title”, web.Title);
                    xmlWriter.WriteAttributeString(“WebTemplateID”, web.WebTemplateId.ToString());
                    xmlWriter.WriteAttributeString(“WebTemplateName”, web.WebTemplate);

                    //close the site(web) element
                    xmlWriter.WriteEndElement();
                }
            }       
            }
        catch (Exception webError)
            {
                //if an error occurs write the error message to
                //an error element   
                xmlWriter.WriteElementString(“error”, webError.Message);
            }
        //close the webs element   
        xmlWriter.WriteEndElement();     
    }