easyui下拉框动态级联加载的示例代码

<span>学院名称：</span> <input class="easyui-combobox" style="width:30%;" id="collegeName"> <span>课程名称：</span> <input class="easyui-combobox" style="width:30%;" id="courseName"><br/> 

$(function() {       // 下拉框选择控件，下拉框的内容是动态查询数据库信息    $('#collegeName').combobox({         url:'${pageContext.request.contextPath}/loadInstitution',         editable:false, //不可编辑状态        cache: false,        panelHeight: '150',        valueField:'id',          textField:'institutionName',             onHidePanel: function(){       $("#courseName").combobox("setValue",'');//清空课程       var id = $('#collegeName').combobox('getValue');           //alert(id);             $.ajax({       type: "POST",       url: '${pageContext.request.contextPath}/loadCourse?id=' + id,       cache: false,       dataType : "json",       success: function(data){       $("#courseName").combobox("loadData",data);            }         });           } });          $('#courseName').combobox({       //url:'itemManage!categorytbl',       editable:false, //不可编辑状态      cache: false,      panelHeight: '150',//自动高度适合      valueField:'id',        textField:'courseName'      });     }); 

@RequestMapping("/loadInstitution")   /**    * 加载学院    * @param     * @param     * @return void    * @exception/throws [违例类型] [违例说明]    * @see     [类、类#方法、类#成员]    * @deprecated    */   public void loadInstitute(HttpServletRequest request,       HttpServletResponse response) throws Exception {     try {       JackJsonUtils JackJsonUtils = new JackJsonUtils();       List<Institution> institutionList = institutionBean           .queryAllColleage();       System.out.println("学院list大小=====" + institutionList.size());       String result = JackJsonUtils.BeanToJson(institutionList);       System.out.println(result);       JsonUtils.outJson(response, result);     } catch (Exception e) {       logger.error("加载学院失败", e);     }   }    @RequestMapping("/loadCourse")   /**    * 动态加载课程    *    *    * @param     * @param     * @return void    * @exception/throws [违例类型] [违例说明]    * @see     [类、类#方法、类#成员]    * @deprecated    */   public void loadCourse(HttpServletRequest request,       HttpServletResponse response) throws Exception {     JackJsonUtils JackJsonUtils = new JackJsonUtils();     String id = request.getParameter("id");     System.out.println("学院id====" + id);     try {       if(id != null && id != ""){         List<CourseInfo> listCourseInfoList = courseBean             .queryAllCourseInfos(id);         System.out.println("课程list大小=====" + listCourseInfoList.size());         String result = JackJsonUtils.BeanToJson(listCourseInfoList);         System.out.println(result);         JsonUtils.outJson(response, result);       }     } catch (Exception e) {       logger.error("加载课程失败", e);     }   }