jsp连接数据库以及前端网页实现对数据库的增删改查_jsp进行增删改操作后前段更新数据-优快云博客

本文链接：https://blog.youkuaiyun.com/ting_163/article/details/75805464

//web首页，显示登录注册页面

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>

<head>
<title>QQ登录页面</title>
<style type="text/css">
</style>
</head>

<body>
   <form method="post">
       账户:<input type="text" name="name"><br/>
       密码:<input type="text" name="password"><br/>
       验证码<input type="text"><img src="picture.jsp" /><br/>
       <button οnclick="form.action='dologin.jsp'">登录</button>
       <button οnclick="form.action='doadd.jsp'">注册</button>
   </form>
</body>

//实现注册功能

<%@page import="java.sql.PreparedStatement"%>
<%@page import="java.sql.Connection"%>
<%@page import="java.sql.DriverManager"%>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
   request.setCharacterEncoding("utf-8");
   String name = request.getParameter("name");
   String password = request.getParameter("password");
   Class.forName("com.mysql.jdbc.Driver");
   String url = "jdbc:mysql:///mysql_01";
   String usename = "root";
   String usepasword ="root";
   Connection conn = DriverManager.getConnection(url , usename , usepasword);
   String sql ="insert into worker values(null,?, ?)";
   PreparedStatement ps = conn.prepareStatement(sql);
   ps.setString(1,name);
   ps.setString(2,password);
   ps.executeUpdate();
   conn.close();
   response.sendRedirect("list.jsp");
%>

//从数据库中获取所有用户数据

<%@page import="java.sql.ResultSet"%>
<%@page import="java.sql.PreparedStatement"%>
<%@page import="java.sql.Connection"%>
<%@page import="java.sql.DriverManager"%>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<h3 align="center">数据列表</h3>
<table align="center" border="1px" width="300px" height="20px">
<%
   Class.forName("com.mysql.jdbc.Driver");
   String url = "jdbc:mysql:///mysql_01";
   String usename = "root";
   String usepassword ="root";
   Connection conn = DriverManager.getConnection(url , usename , usepassword);
   String sql = "select * from worker";
   PreparedStatement ps=conn.prepareStatement(sql);
   ResultSet rs = ps.executeQuery();
   while(rs.next()){
%>
   <tr align="center">
       <td><%=rs.getInt("id") %></td>
       <td><%=rs.getString("name") %></td>
       <td><%=rs.getString("password") %></td>
       <td><a href="del.jsp?name=<%=rs.getInt("id") %>">删除</a></td>
       <td><a href="update.jsp?name=<%=rs.getInt("id") %>">修改</a></td>
   </tr>
<%
   }
   conn.close();
%>
</table>
<a href="index.jsp">返回主页面</a>

//实现对数据的删除功能

<%@page import="java.sql.PreparedStatement"%>
<%@page import="java.sql.Connection"%>
<%@page import="java.sql.DriverManager"%>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
   String id =request.getParameter("name");
   Class.forName("com.mysql.jdbc.Driver");
   String url = "jdbc:mysql:///mysql_01";
   String usename = "root";
   String usepassword ="root";
   Connection conn = DriverManager.getConnection(url,usename , usepassword);
   String sql = "delete from worker where id="+id;
   PreparedStatement ps = conn.prepareStatement(sql);
   ps.executeUpdate();
   conn.close();
   response.sendRedirect("list.jsp");
%>

//数据库实现对要修改的数据的查询

<%@page import="java.sql.PreparedStatement"%>
<%@page import="java.sql.Connection"%>
<%@page import="java.sql.DriverManager"%>
<%@page import="java.net.ConnectException"%>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
   request.setCharacterEncoding("utf-8");
   String id = request.getParameter("id");
   String password = request.getParameter("password");
   Class.forName("com.mysql.jdbc.Driver");
   String url = "jdbc:mysql:///mysql_01";
   String usename ="root";
   String usepassword ="root";
   Connection conn = DriverManager.getConnection(url,usename,usepassword);
   String sql = "update worker set password=? where id=?";
   PreparedStatement ps = conn.prepareStatement(sql);
   ps.setString(1,password);
   ps.setInt(2,Integer.parseInt(id));
   ps.executeUpdate();
   conn.close();
   response.sendRedirect("list.jsp");
%>

//找到数据库中对应的要修改的数据，并对其进行修改

<%@page import="java.sql.ResultSet"%>
<%@page import="java.sql.PreparedStatement"%>
<%@page import="java.sql.Connection"%>
<%@page import="java.sql.DriverManager"%>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>

<%
   request.setCharacterEncoding("utf-8");
   String id = request.getParameter("name");
   Class.forName("com.mysql.jdbc.Driver");
   String url = "jdbc:mysql:///mysql_01";
   String usename ="root";
   String usepassword ="root";
   Connection conn = DriverManager.getConnection(url,usename , usepassword);
   String sql ="select * from worker where id=?";
   PreparedStatement ps = conn.prepareStatement(sql);
   //将字符串的id转换成int型的id
   ps.setInt(1, Integer.parseInt(id));
   ResultSet rs= ps.executeQuery();
   if(rs.next()){
%>
   <form align="center" method="post">
       <input type="hidden" name="id" value="<%=rs.getInt("id") %>"><br/>
       密码:<input type="text" name ="password" value="<%=rs.getString("password") %>">
       <button οnclick="form.action='doupdate.jsp'">修改</button>
   </form>

<%
   }
%>

//登录功能实现从前端获取的数据与数据库的数据进行对比

<%@page import="java.sql.ResultSet"%>
<%@page import="java.sql.PreparedStatement"%>
<%@page import="java.sql.DriverManager"%>
<%@page import="java.sql.Connection"%>
<%@page pageEncoding="utf-8" %>
<%
   String name = request.getParameter("name");
   String password = request.getParameter("password");
   Class.forName("com.mysql.jdbc.Driver");
   String url = "jdbc:mysql://localhost:3306/mysql_01";
   String servername = "root";
   String serverpassword = "root";
   Connection conn = DriverManager.getConnection(url , servername , serverpassword);
   String sql = "select * from worker";
   PreparedStatement ps = conn.prepareStatement(sql);
   ResultSet rs = ps.executeQuery();
   boolean flag = false;
   while(rs.next()){
       if(name!=null&&(rs.getString("name")).equals(name)){
           if(password!=null&&(rs.getString("password")).equals(password)){
               flag = true ;
               break;
           }else{
               flag = false;
           }
       }else{
           flag = false;
       }
   }

   //对flag进行判断
   if(flag){
%>
       <script>
           window.location="login.jsp";
       </script>
<%
   }else{
%>
       <script>
           window.location="Client.jsp";
       </script>
<%
   }
%>

//跳转登录成功页面