session保存用户登录
< %@ 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 > Insert title here </ title > </ head > < body > < % session.invalidate (); % > < form action ="yanzheng.jsp" method ="post" > 用户名: < input type ="text" name ="yonghu" > 密码: < input type ="password" name ="mima" > < input type ="submit" value ="登录" > </ form > </ body > </ html > < %@ page language =