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jsp第六周作业

1.安装MySQL数据库,建立用户表 uid uname upwd 并插入3条数据

2.制作jsp登录页面 login.jsp 提交到dologin.jsp,使用jdbc连数据库,判断输入的用户名密码是否存在

3.如果存在,把用户名保存在SESSION中,跳转到welcome.jsp,welcome.jsp中读取session中的用户名,显示欢迎你xxx

4.若不存在,跳到登录页面。

 

//连接数据库

 1 package session;
 2 
 3 import java.sql.Connection;
 4 import java.sql.DriverManager;
 5 import java.sql.PreparedStatement;
 6 import java.sql.ResultSet;
 7 import java.sql.SQLException;
 8 
 9 
10 public class Datalink {
11 
12 
13     //获取连接
14     protected Connection getConnection(){
15         Connection conn=null;
16             try {
17                 Class.forName("com.mysql.jdbc.Driver");
18                 // 2.建立连接
19                 conn = DriverManager.getConnection(
20                         "jdbc:mysql://localhost:3306/mysql", "root", "root");
21             } catch (Exception e) {
22                 e.printStackTrace();
23             } 
24             return conn;
25     }    
26     
27 
28     //关闭连接
29     protected void closeAll(Connection con,PreparedStatement ps,ResultSet rs){        
30     try {
31         if(rs != null)
32             rs.close();
33         if(ps != null)
34             ps.close();
35         if(con != null)
36             con.close();
37         
38         } catch (SQLException e) {
39             e.printStackTrace();
40         }
41     }
42     
43 }

 1 <%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
 2 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
 3 <html>
 4   <head>
 5     <title>用户登录</title>
 6   </head>
 7   <body>
 8         <form name="form1" method="post" action="dologin.jsp">
 9             用户名:
10             <input type="text" name="userName">
11             密码:
12             <input type="password" name="pwd">
13             <input type="submit" value="登录">
14         </form>
15   </body>
16 </html>
 1 <%@ page contentType="text/html;charset=UTF-8" language="java"%>
 2 <html>
 3 <head>
 4 <title>Title</title>
 5 </head>
 6 <body>
 7     <%
 8         String uname = request.getParameter("username");
 9         String upwd = request.getParameter("password");
10 
11         String realUname = "";
12         String reaslPassword = "";
13 
14         Class.forName("com.mysql.jdbc.Driver");
15 
16         Connection connection = DriverManager.getConnection(
17                 "jdbc:mysql://localhost:3306/mysql", "root", "root");
18 
19         PreparedStatement preparedStatement = connection
20                 .prepareStatement("SELECT * FROM dl where uname = ?");
21         preparedStatement.setString(1, uname);
22 
23         ResultSet rs = null;
24         try {
25             rs = preparedStatement.executeQuery();
26         } catch (SQLException e) {
27             e.printStackTrace();
28         }
29 
30         while (rs.next()) {
31             realUname = rs.getString("uname");
32             reaslPassword = rs.getString("upwd");
33         }
34 
35         if (uname.equals(realUname) && upwd.equals(reaslPassword)
36                 && inputVcode.equals(inputVcode)) {
37             HttpSession httpSession = request.getSession();
38             httpSession.setAttribute("username", uname);
39             httpSession.setAttribute("password", upwd);
40             response.sendRedirect("welcome.jsp");
41         } else {
42             response.sendRedirect("index.jsp");
43         }
44     %>
45 </body>
46 </html>
 1 <%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
 2 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
 3 <html>
 4 <head>
 5 <title>session</title>
 6 </head>
 7 
 8 <body>
 9     <%
10         String uname = (String) session.getAttribute("uname");
11         if (uname == null) {
12             response.sendRedirect("index.jsp");
13         }
14     %>
15     欢迎您!<%=uname%>
16 </body>
17 </html>

 

 

 

posted @ 2021-04-11 16:19  世界丶已黑白  阅读(43)  评论(0编辑  收藏  举报