Ajax二级联动菜单实现原理及代码
index.jsp: 复制代码 代码如下: <%@ page language="java" pageEncoding="UTF-8"%> 二级菜单联动演示 SelectServlet: 复制代码 代码如下: package com; import java.io.IOException; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; /*** * * @author zdw * */ public class SelectServlet extends HttpServlet { private static final long serialVersionUID = 1L; public SelectServlet() { super(); } public void destroy() { super.destroy(); } public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // response.setCharacterEncoding("GBK"); response.setContentType("text/xml"); response.setHeader("Cache-Control", "no-cache"); request.setCharacterEncoding("GBK"); response.setCharacterEncoding("UTF-8"); String targetId = request.getParameter("id").toString(); System.out.println(targetId); // 获得请求中参数为id的值 String xml_start = ""; String xml_end = ""; String xml = ""; if (targetId.equalsIgnoreCase("0")) { xml = ""; } else if (targetId.equalsIgnoreCase("1")) { xml = ""; xml += ""; xml += ""; xml += ""; } else if (targetId.equalsIgnoreCase("2")) { xml = ""; xml += ""; xml += ""; xml += ""; } else {// 如果是3,则返回下面的字符 xml = ""; xml += ""; xml += ""; xml += ""; } String last_xml = xml_start + xml + xml_end; response.getWriter().write(last_xml); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } public void init() throws ServletException { } } web.xml: 复制代码 代码如下: SelectServlet com.SelectServlet SelectServlet /select index.jsp