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 index.jsp 提交到ok.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，跳转到yes.jsp

数据库

 

 

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<html>
<body>
    <form action="ok.jsp" method=post>
        用户名： <input type="text" name="uname" /> <br> 密 码 ： <input
            type="text" name="upwd" /><br> 验证码： <input type="text"
            name="yzm" /> 11+30=?<br> <input type="submit" name="dl"
            value="登录" /> <br>
    </form>
    <% %>
    <script>         //弹窗提示
            alert('输入密码或用户名错误');
            </script>

</body>
</html>
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%@ page import="java.sql.*"%>
<html>
<body>

    <%
        request.setCharacterEncoding("utf-8");
        String name = request.getParameter("uname");
        String pwd = request.getParameter("upwd");
        String yz = request.getParameter("yzm");

        //request.getRequestDispatcher("index.jsp").forward(request,response);
        PreparedStatement pre = null;
        Connection con = null;
        Statement sql;
        ResultSet rs;
        request.setCharacterEncoding("utf-8");

        try {
            Class.forName("com.mysql.jdbc.Driver");
        } catch (Exception e) {
            out.print("<h1>加载错误" + e);
        }

        String user = "root";
        String password = "root";

        con = DriverManager.getConnection(
                "jdbc:mysql://127.0.0.1:3306/mysql", user, password);

        try {
            sql = con.createStatement();

            String SQLL = "select * from sjk where uname=? and upwd=?";
            pre = con.prepareStatement(SQLL);
            pre.setString(1, name);
            pre.setString(2, pwd);

            rs = pre.executeQuery();

            if (rs.next()) {
                String na = rs.getString(2);
                session.setAttribute("uname", na);
                response.sendRedirect("yes.jsp");

            } else {
                response.sendRedirect("index.jsp");
            }
        } catch (SQLException e) {
            out.print("<h1>查询错误" + e);
        }
    %>

</body>
</html>
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<html>
<body>

    欢迎
    <%=session.getAttribute("uname")%>
    来到你的世界！
</body>
</html>

 

 

 

 

 

posted @ 2021-04-09 23:06  你的名字！  阅读(335)  评论(0)    收藏  举报