jsp登录页面的简单实例 雏形
<%@ 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>欢迎页面</title> </head> <body> <% session.invalidate();//销毁session %> <a href="https://www.jb51.net/denglu.jsp" >亲，请登录</a> <a href="https://www.jb51.net/zhuce.jsp">注册</a> </body> </html>
欢迎界面：
尚未注册，直接登录的时候：
<%@ 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>登录</title> </head> <body> <form action="test_denglu.jsp" method="post"> <table> <tr> <td colspan="2"><font size="24">OO登录</font></td></tr> <tr> <td>用户名：</td> <td><input type="text"></td></tr> <tr> <td> 密 码：</td> <td> <input type="password"></td></tr> <tr><td colspan="2"> <input type="submit" value="登录"> </td></tr> </table> </form> </body> </html>
进入注册界面：
<%@ 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>注册</title> </head> <body> <form action="test_zhuce.jsp" method="post"> <table> <tr> <td colspan="2"><font size="24">OO注册</font></td></tr> <tr> <td>用户名：</td> <td><input type="text"></td></tr> <tr> <td> 密 码：</td> <td> <input type="password"></td></tr> <tr><td colspan="2"> <input type="submit" value="提交"> </td></tr> </table> </form> </body> </html>
注册成功，跳转登录界面：
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" import="java.sql.*"%> <!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>检测跳转中</title> </head> <body> <% String name = new String(request.getParameter("username").getBytes("ISO-8859-1"),"UTF-8"); String pw = request.getParameter("password"); String str = "select * from USERS WHERE username = '" + name + "'"; String str1 = "insert into users values(xuhao.nextval,'" + name + "','" + pw +"')"; try{ //连接数据库 Connection conn = null; Class.forName("oracle.jdbc.driver.OracleDriver"); String strURL = "jdbc:oracle:thin:@localhost:1521:SP"; conn = DriverManager.getConnection(strURL, "test", "123"); System.out.println("数据库连接成功"); Statement st = conn.createStatement(); ResultSet rs = st.executeQuery(str); if(rs.next()){ if(name.equals(rs.getString(2))){ out.println("对不起，用户名已使用。"); out.println("<br>建议使用用户名：" + name +"99"); response.setHeader("refresh", "5;URL=https://www.jb51.net/zhuce.jsp"); } }else{ int a = st.executeUpdate(str1); if(a == 1){ out.println("恭喜你，注册成功"); session.setAttribute("username", name); response.setHeader("refresh", "3;URL=https://www.jb51.net/denglu.jsp"); } } rs.close(); st.close(); conn.close(); }catch(Exception e){ e.printStackTrace(); } %> <br><br> </body> </html>
登录时，密码出错：5秒后重新登录
账号密码输入正确，进入主页面：