关于通过Ajax给下拉列表赋值

后台数据封装如下：// 用于添加下拉列表值
if ("getItem".equals(modle)) {
response.setContentType("text/xml");
response.setCharacterEncoding("GB18030");
response.setHeader("Cache-Control", "no-cache");
StringBuffer sb = new StringBuffer(" <lzg> <sun>所有工程 </sun>");
ArrayList list = new ArrayList();
DataOperat dataop = new DataOperat();
sql = "select project_name from projects";
list = dataop.findlist(sql);
if(!list.isEmpty()){
                for(int i=0;i <list.size();i++){
                HashMap hash=(HashMap)list.get(i);
                sb.append(" <sun>"+hash.get("project_name").toString()+" </sun>");
                }
                }
sb.append(" <mone>所有协做单位 </mone>");
sql = "SELECT unit_name from coopunit c";
list = dataop.findlist(sql);
if(!list.isEmpty()){
                for(int i=0;i <list.size();i++){
                HashMap has