jsp用户登录验证

青旅半醒 2022-05-27 03:16 259阅读 0赞

项目结构

![20180410171232460][]

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
    <%
    String path = request.getContextPath();
    String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
    %>
    
    <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
    <html>
      <head>
        <base href="<%=basePath%>">
        
        <title>用户登录</title>
        
    	<meta http-equiv="pragma" content="no-cache">
    	<meta http-equiv="cache-control" content="no-cache">
    	<meta http-equiv="expires" content="0">    
    	<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    	<meta http-equiv="description" content="This is my page">
    	
      </head>
      <body>
        <form method="post" action="loginCheck.jsp">
        <center>
            	<h4>xxx学生管理系统</h4>
            	<table>
        		<tr>
        		<td>用户名:</td>
        		<td><input type="text" name="username"></td>
        		</tr>
        		<tr>
        		<td>密    码:</td>
        		<td><input type="password" name="password"></td>
        		</tr>
        		<tr>
        		<td></td>
        		<td><input type="submit" value="登录" οnclick="check()"> <input type="reset" value="重置"></td>
        		</tr>
        	</table>
        </center>
        </form>
      </body>
    </html>

界面效果

![20180410171445615][]

loginCheck.jsp

index.jsp

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
    <%
    String path = request.getContextPath();
    String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
    %>
    
    <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
    <html>
      <head>
        <base href="<%=basePath%>">
        
        <title>学生管理系统</title>
    	<meta http-equiv="pragma" content="no-cache">
    	<meta http-equiv="cache-control" content="no-cache">
    	<meta http-equiv="expires" content="0">    
    	<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    	<meta http-equiv="description" content="This is my page">
    	
    	<style type="text/css">
    		ul{
    			list-style-type: none;
    			background-color:#333;
    			margin:0;
    			padding:0;
    		}
    		li a{
    			text-decoration: none;
    			color:white;
    		}
    		li{
    			display: inline;
    			padding: 10px 16px;
    		}
    	</style>
      </head>
      <body>
      <%
      	String username=session.getAttribute("user").toString();
       %>
        <ul>
        	<li><a href="">学生管理</a></li>
        	<li><a href="">课程管理</a></li>
        	<li><a href="">成绩管理</a></li>
        </ul>
         <p><font color="red"><%=username%></font>欢迎您,使用学生管理系统！</p>
      </body>
    </html>

界面效果

![20180410172234963][]

loginError.jsp

DbHelper类

package com;
    import java.sql.Connection;
    import java.sql.DriverManager;
    import java.sql.PreparedStatement;
    import java.sql.ResultSet;
    import java.sql.Statement;
    public class DbHelper {
    	private Connection conn=null;
    	private Statement stmt=null;
    	private ResultSet rest=null;
    	private PreparedStatement prst=null;
    	public Connection getConn(){
    		try{
    			String url="jdbc:mysql://localhost:3306/student";
    			String username="root";
    			String password="root";
    			Class.forName("com.mysql.jdbc.Driver");
    			conn=DriverManager.getConnection(url,username,password);
    			if(conn!=null){
    				System.out.println("数据库连接成功。");
    			}else{
    				System.out.println("数据库连接失败。");
    			}
    		}catch(Exception e){
    			e.printStackTrace();
    		}
    		return conn;
    	}
    	public ResultSet selectUser(String name,String pwd){
    		try{
    			conn=getConn();
    			String sql="select * from user where username=? and password=?";
    			prst=conn.prepareStatement(sql);
    			prst.setString(1, name);
    			prst.setString(2, pwd);
    			rest=prst.executeQuery();
    		}catch(Exception e){
    			e.printStackTrace();
    		}
    		return rest;
    	}
    }

[20180410171232460]: /images/20220527/3f4dc82948b84f31bca0e4a8cf33d054.png
[20180410171445615]: /images/20220527/db5e00c2484248e98e2b7c490a01333e.png
[20180410172234963]: /images/20220527/424b4b7237ad41afb457c5a7920c24f7.png