代码打卡

最新推荐文章于 2023-04-25 21:41:14 发布

卞浩

最新推荐文章于 2023-04-25 21:41:14 发布

阅读量935

点赞数

CC 4.0 BY-SA版权

本文链接：https://blog.youkuaiyun.com/ngwth_nail/article/details/82934459

1、

<%@ page language="java" import="java.util.*" 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>登录界面</title>
<script type="text/javascript">
function change(){
var img=document.getElementById("verify");
img.src="VerifyCodeServlet?a="+new Data().getTime();
}
</script>
</head>

</body>
</html>

2、<%@ page language="java" import="java.util.*"
   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>注册界面</title>
</head>
<body>
   <center>
       <div>
           <h1>注册</h1>
           <form action="RegistServlet" method="post">
               请输入账号:<input type="text" name="username"><br /> 请输入密码:<input
                   type="password" name="password"><br /> 请确认密码:<input
                   type="password" name="rpsw"><br /> <input type="submit"
                   value="注册">
           </form>
           <font color="green" size="2">${msg }</font>
       </div>
   </center>
</body>
</html>

3、

package servlets;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import beans.UserDao;
@WebServlet("/LoginServlet")
public class LoginServlet extends HttpServlet {
private static final long serialVersionUID = 1L;

   protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
       request.setCharacterEncoding("utf-8");
       response.setContentType("text/html;charset=utf-8");
       String username=request.getParameter("username");
       String password=request.getParameter("password");
   //   String verifyc=request.getParameter("verifycode");
   // String svc=(String)request.getSession().getAttribute("sessionverify");
   String psw=new UserDao().findUsername(username);
   /* if(!svc.equalsIgnoreCase(verifyc)) {
       request.setAttribute("msg", "验证码错误!");
       request.getRequestDispatcher("/index.jsp").forward(request, response);
       return ;
   }*/
   if(psw==null) {
       request.setAttribute("msg", "用户还未注册!");
       request.getRequestDispatcher("/index.jsp").forward(request, response);
       return;
   }
   if(psw!=null && !psw.equals(password)) {
       request.setAttribute("msg", "密码错误，请重新输入！");
       request.getRequestDispatcher("/index.jsp").forward(request, response);
       return ;
   }
   if(psw.equals(password)) {
       request.setAttribute("msg", "用户:"+username+",欢迎访问");
       request.getRequestDispatcher("/index.jsp").forward(request, response);
   }
   }

}

4、

package servlets;

@WebServlet("/RegistServlet")
public class RegistServlet extends HttpServlet {
   private static final long serialVersionUID = 1L;

   protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
       request.setCharacterEncoding("utf-8");
       response.setContentType("text/html;charset=utf-8");
       String username=request.getParameter("username");
       String password=request.getParameter("password");
       String rpsw=request.getParameter("rpsw");
       if(username==null || username.trim().isEmpty()) {
           request.setAttribute("msg", "账号不能为空");
           request.getRequestDispatcher("/regist.jsp").forward(request, response);
           return;
       }
       if(password==null || password.trim().isEmpty()) {
           request.setAttribute("msg", "密码不能为空");
           request.getRequestDispatcher("/regist.jsp").forward(request, response);
           return ;
       }
       if(!password.equals(rpsw)) {
           request.setAttribute("msg", "两次输入的密码不同");
           request.getRequestDispatcher("/regist.jsp").forward(request, response);
           return ;
       }
       new UserDao().addUser(username, password);
       request.setAttribute("msg", "恭喜:"+username+",注册成功");
       request.getRequestDispatcher("/regist.jsp").forward(request, response);
   }

}

5、
package beans;
import java.sql.*;
public class UserDao {
   public String findUsername(String username) {
       String psw=null;
       try {
           Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
           Connection conn=DriverManager.getConnection("jdbc:sqlserver://localhost:1433;DatabaseName=students;user=Sa;password=pw447451");
           String sql="select * from zc where name=?";
           PreparedStatement pstmt=conn.prepareStatement(sql);
           pstmt.setString(1, username);
           ResultSet rs=pstmt.executeQuery();
           if(rs==null) {
               return null;
           }
           if(rs.next()) {
               psw=rs.getString("password");
           }
           else psw=null;
           pstmt.close();
           conn.close();
       }catch(Exception e) {

       }
       return psw;


   }
   public void addUser(String username, String psw) {
       try {
       Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
       Connection conn=DriverManager.getConnection("jdbc:sqlserver://localhost:1433;DatabaseName=students;user=Sa;password=pw447451");
       String sql="insert into zc values(?,?)";
       PreparedStatement pstmt=conn.prepareStatement(sql);
       pstmt.setString(1, username);
pstmt.setString(2, psw);
pstmt.executeUpdate();
pstmt.close();
conn.close();
   }catch(Exception e) {

   }
   }

}