Jsp第五次作业

<%@ page language="java" contentType="text/html; charset=utf-8"
    pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>登陆页面</title>
<style type="text/css">
 body{font-size: 16px;}
 </style>
 <script type="text/javascript">
 function mycheck() {
 //判断用户名是否为空
 if (form1.userName.value==""){
alert("用户名不能为空，请输入用户名！");
 form1.userName.focus();
 return;
 }
 //判断密码是否为空
 if (form1.password.value=="") {
 alert("密码不能为空，请输入密码！");
 form1.password.focus();
 return;
 }
//判断验证码是否为空
 if (form1.validationCode.value==""){
alert("验证码不能为空，请输入验证码!");
 form1.validationCode.focus();
 return;
 }
 //判断验证码是否正确
 if (form1.validationCode.value != form1.validationCode1.value) {
 alert("请输入正确的验证码!!");
 form1.validationCode.focus();
 return;
 }
 form1.submit1();
 }
 </script>
 </head>
 <body bgcolor="pink">
 <form action="loginCheck.jsp" name="form1" method="post">
 用户名：<input type="text" name="userName" size="16">
 <br> 密&nbsp;&nbsp;&nbsp;&nbsp;码：
 <input type="password" name="password" size="18">
 <br>
 验证码：<input type="text" name="validationCode" 
 onKeyDown="if(event.keyCode==13){form1.submit.focus();}" size="6">
 <%
 int intmethod1 = (int) ((((Math.random()) * 7)) - 1);
 int intmethod2 = (int) ((((Math.random()) * 7)) - 1);
 int intmethod3 = (int) ((((Math.random()) * 7)) - 1);
 int intmethod4 = (int) ((((Math.random()) * 7)) - 1);
 //将得到的随机数进行连接
  String intsum=intmethod1+""+intmethod2+intmethod3+intmethod4;
   %> 
   <input type="hidden" name="validationCode1" value="<%=intsum%>">
   <img style="height:20px;weight:20px" src="images/<%=intmethod1 %>.png">
   <img style="height:20px;weight:20px" src="images/<%=intmethod2 %>.png">
   <img style="height:20px;weight:20px" src="images/<%=intmethod3 %>.png">
   <img style="height:20px;weight:20px" src="images/<%=intmethod4 %>.png">
 <br>
 <input type="submit" name="submit1" value="登录" onClick="mycheck()">
 &nbsp; 
 <input type="reset" value="重置">
 </form>
 </body>
</html>

loginCheck.jsp

<%@ page language="java" contentType="text/html; charset=utf-8"
    pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>处理登陆页面的数据</title>
</head>
 <body bgcolor="pink">
 <% 
//设置请求的编码，用于解决中文乱码问题
 request.setCharacterEncoding("UTF-8");
String name =request.getParameter("userName");
String    password=request.getParameter("password");
if(request.getParameter("validationCode1").equals(request.getParameter("validationCode")))//判断输入的和随机的是否相等        
{            
if(name.equals("gjm")&&(password.equals("123456"))){            
//把用户名到session中            
session.setAttribute("userName",name);        //若用户名密码正确，将用户名添加到对象中    
response.sendRedirect("main.jsp");            
}else{            
response.sendRedirect("login.jsp");        //若用户名密码不正确执行    
}            
}else{            
response.sendRedirect("login.jsp");    //若验证码不相等执行        
}            
%>            
</body>            
</html>

main.jsp

<%@ page language="java" contentType="text/html; charset=utf-8"
    pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>主页面</title>
 </head>
 <body bgcolor="pink">
 <%
 //获取保存在session中的用户名
 String name=(String)session.getAttribute("userName");
 %>
 您好<%=name%>,欢迎您访问！<br>
 <a href="exit.jsp">[退出系统]</a>
 </body>
 </html>

exit.jsp

<%@ page language="java" contentType="text/html; charset=utf-8"
    pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>退出系统</title>
</head>
 <body>
 <%
 session.invalidate();//销毁session
response.sendRedirect("login.jsp");//再次去登陆页面
 %>
 </body>
</html>