最近看到有的朋友对 servlet 传值和取值有疑惑，针对次问题在此发表下在servlet中传值和取值操作
html代码：
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html> <head> <title>东北大亨 用户校验的ajax</title> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="this is my page"> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> <!--<link rel="stylesheet" type="text/css" href="./styles.css">--> <script type="text/javascript" src="jslib/jquery.js"></script> <script type="text/javascript" src="jslib/get.js"> </script> </head> <body> 用户名校验的ajax实例,请输入用户名: <input type="text" id="userName"/> <input type="button" value="校验" onclick="verify()"/> <div id="result"> </div> </body></html>测试 get.js
function setou(){// document.getElementsByName("userName");// document.getElementById("userName");// alert("userName)");// jquery的查找节点的值的方式 var jqueryObj = $("#userName"); var userName = jqueryObj.val();// alert(userName); // 这里传的参数为：name。这里可以根据需要定义自己需要的参数变量 // 这里传什么参数变量在
testServlet中用什么参数名称接值。 $.get("testServlet?name=" +userName,null,callback);}function callback(data){// alert("服务器端的数据回来了");// alert(data); var resultObj = $("#result"); resultObj.html(data); alert("");}testServlet.java
package cn.itcast.project;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletResponse;import javax.servlet.http.HttpServletRequest;import java.io.IOException;import java.io.PrintWriter;import javax.servlet.ServletException;public class testServletextends HttpServlet{ /** * */ private static final long serialVersionUID = 1L; protected void doGet(HttpServletRequest request,HttpServletResponse response) throws ServletException,IOException { try { // request.setCharacterEncoding("UTF-8"); response.setContentType("text/html;charset=utf-8"); PrintWriter out = response.getWriter(); // 取值的参数根据赋值的参数进行取值。这里的参数用的是name String name = request.getParameter("name"); if(name == null || name.length() == 0) { out.println("用户名不能为空"); }else { if(name.equals("东北大亨（northesttycoon）")) { out.println("用户名["+name+"]已经存在,请使用其他账户登录"); }else { out.println("用户名["+name+"]尚未存在,可以使用该用户登录"); } } }catch(Exception ex) { ex.printStackTrace(); } } protected void doPost(HttpServletRequest request,HttpServletResponse response) throws ServletException,IOException { doGet(request,response); }