function CustomEvent(sEventName)
        {
                if(sEventName == "SelectModified")
               {
                        var axMxDrawX1 = document.getElementById("MxDrawXCtrl");
                        var pParam = axMxDrawX1.CustomEventParam();
                        var i = 0;
                        for(;i < pParam.Count;i++)
                        {
                              // 选择的实体对象id.
                              var id = pParam.AtLong(i);
                        }
                        alert(pParam.Count);
               }

        }