主要用Session来实现
用户登录成功后,设置一个Session范围属性,然后在其他需要验证的页面判断是否存在此Session属性范围,存在则表示正常登录
过的合法用户,不存在给予提示,跳转登录页重新登录,登录后再进行注销操作
只要有这几个页面
login.jsp
welcome.jsp
logout.jsp
编写表单并执行验证login.jsp
<%@ page language= "java" contentType= "text/html" pageEncoding= "GBK" %> <html> <head> <title>测试</title> </head> <body> <form action= "login.jsp" method= "post" > 用户名:<input type= "text" name= "uname" ><br/> 密码:<input type= "password" name= "upass" ><br/> <input type= "submit" value= "登录" > <input type= "reset" value= "重置" > </form> <% String name=request.getParameter( "uname" ); Stirng password=request.getParameter( "upass" ); if (!(name== null || "" .equals(name)||password== null || "" .equals(password))){ if ( "esyzf" .equals(name)&& "123456" .equals(password)){ response.setHeader( "refresh" , "2;url=welcome.jsp" ); session.setAttribute( "userid" ,name); %> <h3>用户登录成功,两秒后跳转到欢迎页面</h3> <h3>如何没有跳转,请按<a href= "welcome.jsp" >这里</a></h3> <% } } %> </body> </html> |
欢迎页 welcome.jsp
<%@ page language= "java" contentType= "text/html" pageEncoding= "GBK" %> <html> <head> <title>测试</title> </head> <body> <% if (session.getAttribute( "userid" )!= null ){ %> <h3>欢迎<%=session.getAttribute( "userid" )%>光临本系统,<a href= "logout.jsp" >注销!</a></h3> <% } else { %> <h3>请先进行系统的<a href= "login.jsp" >登录</a></h3> <% } %> </body> </html> |
登录注销 logout.jsp
<%@ page language= "java" contentType= "text/html" pageEncoding= "GBK" %> <html> <head> <title>测试</title> </head> <body> <% response.setHeader( "refresh" , "2;url=login.jsp" ); //定时跳转 session.invalidate(); //注销 %> <h3>你好,你已经退出本系统,两秒后跳会首页</h3> <h3>如没有跳转,请按<a href= "login.jsp" >这里</a> </body> </html> |