function loadConstants() {
        var ctx = new SP.ClientContext.get_current();
        this.site = ctx.get_site();
         ctx.load(this.site );
        this.web = ctx.get_web();
       var list = web.get_lists().getByTitle('VGuardWebMethodList');
       ctx.load(this.web);
       ctx.executeQueryAsync(Function.createDelegate(this, this.onSuccess),
         Function.createDelegate(this, this.onFail));
         }

      function onSuccess(sender, args) {

        IPC_siteUrl = this.site.get_url();
      alert(IPC_siteUrl );
        IPC_siteId = this.site.get_id();
       alert(IPC_siteId );
    }
      function onFail(sender, args) {
      console.log(args.get_message());
     }
      function callWebServiceMethodAjaxTest() {
    $j.ajax({
            type: "GET",
                           cache: false,
            url: methodUrl,
            contentType: "application/json",
            dataType: 'json',
            beforeSend: function () { },
            complete: function () { },
            error: function (xhr, status, errorThrown) {
                alert(errorThrown);
            },
             success: function (result) {
                alert(result.d);
              }
           });
          }
       </script> ​​