我将实现一个简单的Ajax页面无刷新进行用户验证案例：
效果如下图：
实现主要过程：
在UsersAction类中的checkUser方法中接收并验证前台的表单数据，针对不同情况，返回一个状态码code给jsp页面，然后在ajax1.jsp中通过$.post方法接受后台传递过来的状态码
做出不同的响应。
具体代码如下：
1.实体类
package com.bean; import java.io.Serializable; public class Users implements Serializable { private String uname; private String passwd; public String getUname() { return uname; } public void setUname(String uname) { this.uname = uname; } public String getPasswd() { return passwd; } public void setPasswd(String passwd) { this.passwd = passwd; } public Users(String uname, String passwd) { super(); this.uname = uname; this.passwd = passwd; } public Users() { super(); } }
2.action类
package com.action; import java.io.IOException; import java.io.PrintWriter; import javax.servlet.http.HttpServletResponse; import org.apache.struts2.ServletActionContext; import org.apache.struts2.convention.annotation.Action; import com.bean.Users; public class UsersAction { private Users us; public Users getUs() { return us; } public void setUs(Users us) { this.us = us; } @Action(value="checkUser") public String checkUser() { System.out.println("aaaaaaaaa"); HttpServletResponse response = ServletActionContext.getResponse(); response.setCharacterEncoding("utf-8"); try { PrintWriter out = response.getWriter(); int code = 0; if (us == null) { out.print(0); return null; } else { if (us.getUname() == null || us.getUname().trim().equals("")) { code = 1; out.print(code); return null; } else { if (us.getPasswd() == null || us.getPasswd().trim().equals("")) { code = 2; out.print(code); return null; } else { code = 200; out.print(code); } } } out.flush(); out.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } return null; } }
3.ajax1.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> <% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <base href="<%=basePath%>"> <title>Ajax练习</title> <meta http-equiv="pragma" content="no-cache"> <meta http-equiv="cache-control" content="no-cache"> <meta http-equiv="expires" content="0"> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="This is my page"> <!-- <link rel="stylesheet" type="text/css" href="styles.css"> --> <script type="text/javascript" src="js/jquery-1.9.1.js"></script> <script> $(function() { $("#btok").click(function() { //获取数据 var uname = $("#uname").val(); var passwd = $("#passwd").val(); //将数据组织为json格式 var json = {"us.uname":uname,"us.passwd":passwd}; //进行异步请求 $.post("checkUser.action",json,function(msg){ if(msg == '0') { alert("用户名和密码错误！"); return; } if(msg == '1') { $("#uerror").html("用户名错误！"); return; } else { $("#uerror").html("*"); } if(msg == '2') { $("#perror").html("密码错误！"); return; } else { $("#perror").html("*"); } if(msg == '200') { alert("登陆成功！"); return; } }); }); }); </script> </head> <body> <form name="form1" method="post" action=""> <table width="450" border="1" align="center" cellpadding="1" cellspacing="0"> <tr> <td colspan="2" align="center" valign="middle" bgcolor="#FFFFCC">用户注册</td> </tr> <tr> <td width="88">账号:</td> <td width="352"><label for="uname"></label> <input type="text" name="uname" id="uname"> <span id="uerror" style="color:#F06;">*</span></td> </tr> <tr> <td>密码:</td> <td><label for="passwd"></label> <input type="password" name="passwd" id="passwd"> <span id="perror" style="color:#F06;">*</span></td> </tr> <tr align="center" valign="middle" bgcolor="#FFFFCC"> <td colspan="2"><input type="button" name="button" id="btok" value="确定"> <input type="reset" name="button2" id="button2" value="重置"></td> </tr> </table> </form> <br> </body> </html>