数据库的连接和登录
2017-02-26 18:14 ovols 阅读(416) 评论(0) 编辑 收藏 举报软件工程概论—用户登录界面
程序所需的代码:
<%@ page language="java" import="java.sql.*" 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>登录结果</title> </head> <body> <% Connection conn = null; PreparedStatement pstmt = null; ResultSet rs = null; String driverName = "com.mysql.jdbc.Driver"; String userName = "root"; String userPwd = "123"; String dbName = "hkz"; String url1 = "jdbc:mysql://localhost:3306/" + dbName; String url2 = "?user=" + userName + "&password=" + userPwd; String url3 = "&useUnicode=true&characterEncoding=UTF-8"; String url = url1 + url2 + url3; request.setCharacterEncoding("UTF-8"); Class.forName(driverName); conn = DriverManager.getConnection(url); String sql = "select * from userinfo where user=?"; pstmt = conn.prepareStatement(sql); String user = request.getParameter("userName"); String password = request.getParameter("userPwd"); pstmt.setString(1, user); rs = pstmt.executeQuery(); if(rs.next()) { sql = "select * from userinfo where user=? and pwd=?"; pstmt = conn.prepareStatement(sql); pstmt.setString(1, user); pstmt.setString(2, password); rs = pstmt.executeQuery(); if(rs.next()) { %><center><h1>用户 <%=rs.getString("user")%>登陆成功!</h1></center><% } else { %><center><h1>密码错误!</h1></center><% } } else { %><center><h1>用户名不存在!</h1></center> <%} if(rs != null) { rs.close(); } if(pstmt != null) { pstmt.close(); } if(conn != null) { conn.close(); } %> </body> </html>
<%@ 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"> <script type="text/javascript"> function $(id) { return document.getElementById(id); } function check() { var user = $("user").value; var pwd = $("pwd").value; $("userInfo").innerHTML=""; $("pwdInfo").innerHTML=""; if(user == "") { $("userInfo").innerHTML="用户名不能为空!"; $("user").focus(); return false; } if(pwd == "") { $("pwdInfo").innerHTML="密码不能为空!"; $("pwd").focus(); return false; } return true; } </script> <style type="text/css"> #userInfo{color:red;} #pwdInfo{color:red;} </style> <title>登录</title> </head> <body> <center> <form action="loginResult.jsp" method="post" onsubmit="return check()"> <br><br><br><br><br><br> <table> <tr><td>用户名:</td><td><input type="text" name="userName" id="user"><span id="userInfo" ></span></td></tr> <tr><td>密码:</td><td><input type="password" name="userPwd" id="pwd"><span id="pwdInfo"></span></td></tr> <tr><td></td><td><input type="submit" value="登 录"></td> </table> </form> </center> </body> </html>