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。
<%@ page contentType="text/html;charset="utf-8" language="java" %> <html> <head> <title>登陆 界面</title> <link rel="stylesheet" href="./layui/css/layui.css"> <link rel="stylesheet" href="./css/adminLogin.css"> </head> <body> <div class="wrap"> <img src="img/aaasssa.jpg" class="imgStyle"> <div class="loginForm"> <form action="get.jsp" method="POST"> <div class="logoHead"> </div> <div class="usernameWrapDiv"> <div class="usernameLabel"> <label>用户名 :</label> </div> <div class="usernameDiv"> <i class="layui-icon layui-icon-username adminIcon"></i> <input id="loginUsername" class="layui-input adminInput" type="text" name="name" placeholder="请输入用户名："> </div> </div> <div class="usernameWrapDiv"> <div class="usernameLabel"> <label>密码 :</label> </div> <div class="passwordDiv"> <i class="layui-icon layui-icon-password adminIcon"></i> <input id="loginPassword" class="layui-input adminInput" type="password" name="password" placeholder="请输入输入密码"> </div> </div> <div class="usernameWrapDiv"> <div class="usernameLabel"> <label>验证码 :</label> </div> <div class="cardDiv"> <input id="loginCard" class="layui-input cardInput" type="text" name="card" placeholder="请输入验证码 ： "> </div> <div id="code_box" class="codeDiv">Liu1 </div> </div> <div class="usernameWrapDiv"> <div class="submitLabel"> <label>没有该账号信息<a href="#" id="loginRegister">点击注册</a></label> </div> <div class="submitDiv"> <input id="loginBtn" type="submit" class="submit layui-btn layui-btn-primary" value="登录"></input> </div> </div> </form> </div> </div> <script> var code_box = document.getElementById("code_box"); function refreshCode() { var code = '0123456789qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM', char = '', result = ''; for (var i = 0; i < 4; i++) { var code_index = Math.round(Math.random() * 61); var char = code[code_index]; if (result.toUpperCase().indexOf(char.toUpperCase()) > -1) { i--; continue; //终止本轮循环 进行下一轮 } result += char; } code_box.innerHTML = result; } code_box.onclick = refreshCode; </script> <% String name=""; if(!session.isNew()){ name=(String)session.getAttribute("name"); if (name==null){ name=""; } } %> </body> </html>
<%@ page contentType="text/html;charset=utf-8" language="java" %>
<%@ page language="java" import="java.util.*"%>
<%@ page import ="java.sql.*"%>
<html>
<head>
<title>内容信息界面</title>
</head>
<body>
<%--<%--%>
<%-- String name=request.getParameter("name");--%>
<%-- String password=request.getParameter("password");--%>
<%-- if(name.equals("zs")&&password.equals("123")){--%>
<%--%><p>welcome<%=name%></p><%--%>
<%--}else{--%>
<%--%><p>登陆失败</p><%--%>
<%-- }--%>
<%--%>--%>
<%
PreparedStatement pre = null;
Statement sql;
ResultSet rs;
request.setCharacterEncoding("utf-8");
String Name = request.getParameter("name"); //获取输入的用户名
String Ps = request.getParameter("password"); // 密码
Name.trim();
Ps.trim();
request.setCharacterEncoding("utf-8");
Class.forName("com.mysql.cj.jdbc.Driver");
// 建立连接
Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/jsp_db?serverTimezone=GMT", "root", "135790");
sql =conn.createStatement();
String SQL = "select * from jsp_data where uname=? and upassword=?";
pre=conn.prepareStatement(SQL);
pre.setString(1,Name);
pre.setString(2,Ps);
rs=pre.executeQuery();
if (rs.next()) {
String name = rs.getString(1);
session.setAttribute("name",name);
%><p>欢迎登陆：<%=name%></p><%
}else{%> <p>输入错误，请重新登录</p><a href="index.jsp"><button>返回登录界面</button></a>//输入错后返回登陆界面
<%
}
rs.close();
sql.close();
conn.close();
%>
</body>
</html>