<%@ page contentType="text/html;charset=UTF-8" language="java" %> <%@ page import="java.sql.*" %> <html> <head> <title>JSP读取数据库</title> </head> <body> <table border="1" align="center"> <tr> <th>书号</th> <th>书名</th> <th>作者</th> <th>出版社</th> </tr> <% String url="jdbc:mysql://localhost:3306/hhstu?serverTimezone=Asia/test1"; //自己修改 String user="root";//MySQ帐号 String password="123456";//MYSQL密码 Connection conn ; try { Class.forName("com.mysql.jdbc.Driver"); conn = DriverManager.getConnection(url,user,password); Statement stmt=conn.createStatement(); ResultSet rs=stmt.executeQuery("SELECT * FROM books"); while(rs.next()){ %> <tr> <td><%= rs.getInt("bookid") %></td> <td><%= rs.getString("bookname") %></td> <td><%= rs.getString("writer") %></td> <td><%= rs.getString("publish") %></td> </tr> <% } //end while }//end try catch(Exception ex){ ex.printStackTrace(); } %> </table> </body> </html>修改代码

讲解<%@ page contentType="text/html; charset=utf-8" language="java" import="java.sql." errorPage=""%> <%@ page import="com.dao.BookDAO"%> <%@ page import="com.actionForm.BookForm"%> <%@ page import="java.util."%> <html> <% Collection coll = (Collection) req

charset=utf-8"> <title>图书列表</title> </head> <body> <h2>图书列表</h2> <table border="1" cellspacing="0" cellpadding="0"> <tr> <td>编号</td> <td>书名</td> <td>作者</td> <td>出版社</td> </tr> <% for...

检查<?xml version="1.0" encoding="UTF-8" ?> <%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <%@ page import="java.sql.DriverManager" %> <%@ page import="java.sql.Connection" %> <%! Connection connection = null; try { String url = "jdbc:postgresql://localhost:5432/postgres"; String username = "postgres"; String password = "postgres"; // 获取数据库连接 connection = DriverManager.getConnection(url, username, password); } catch (Exception e) { e.printStackTrace(); } %> <% if (connection != null) { out.println("数据库连接成功！"); } else { out.println("数据库连接失败！"); } %>

该代码片段首先通过<%@ page %>指令设置页面的编码为UTF-8，然后导入了java.sql.DriverManager和java.sql.Connection两个类。在<%! %>标签中，定义了一个connection变量，并在try-catch块中尝试建立与...

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <%@ page import="java.util., java.sql."%> <%@ page import="com.util.SQLConn"%> <%@page import="java.net.HttpURLConnection"%> <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> <%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt" %> <!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>Insert Data</title> </head> <body> <%-- 获取前端数据 --%> <% String username = request.getParameter("username"); String usernum = request.getParameter("usernum"); String stime = request.getParameter("stime"); String people = request.getParameter("people"); %> <%-- 定义SQLConn类和INSERT_SQL常量 --%> <% Connection conn = SQLConn.openDB(); //创建Statement , 执行 SQL 查询 Statement sm=ct.createStatement(); //查询用户名登陆状态 String sql; sql ="select Login from User_ZC where UserId='"+usernum+"' and Login='"+1+"' "; // 执行查询 ResultSet rs = sm.executeQuery(sql); if(rs.next()) { //用户在登陆状态 int dbpass = rs.getInt(1); //System.out.println(dbpass); if(dbpass>0){ //用户合法，可以进行预约}第 31 行。错误信息是 "ct cannot be resolved"。

在代码中，你创建了一个名为 "conn" 的 Connection 对象，但在第 31 行中使用了一个名为 "ct" 的 Statement 对象，这导致了编译错误 "ct cannot be resolved"。你需要将第 31 行中的 "ct" 改为 "conn"，或者在代码中...

<%@ page contentType="text/html;charset=UTF-8" language="java" %> <%@page import="java.sql.*" %> <jsp:useBean id="conn" class="chapt12.ConnDB" scope="page"></jsp:useBean> <% ResultSet rs=conn.executeQuery("select title from info order by id desc"); if (rs.next()){ do { out.print(""+rs.getString(1)+""); }while (rs.next()); }else { out.print("暂无公告信息!"); } %>

1. 首先通过<jsp:useBean>标签引入ConnDB类，ConnDB类是一个JavaBean，用于创建数据库连接和执行SQL语句。 2. 然后调用ConnDB类的executeQuery方法执行SQL语句"select title from info order by id desc"，该语句的...

<%@ page contentType="text/html; charset=utf-8" language="java" import="java.sql." errorPage=""%> <%@ page import="com.dao.BookDAO"%> <%@ page import="com.dao.BookTypeDAO"%> <%@ page import="com.actionForm.BookForm"%> <%@ page import="com.actionForm.BookTypeForm"%> <%@ page import="com.dao.BookCaseDAO"%> <%@ page import="com.actionForm.BookCaseForm"%> <%@ page import="com.dao.PublishingDAO"%> <%@ page import="com.actionForm.PublishingForm"%> <%@ page import="java.util."%> <html> <% String str = null; BookTypeDAO bookTypeDAO = new BookTypeDAO(); Collection coll_type = (Collection) bookTypeDAO.query(str); if (coll_type == null || coll_type.isEmpty()) { out.println("<script>alert('请先录入图书类型信息!');history.back(-1);</script>"); } else { Iterator it_type = coll_type.iterator(); int typeID = 0; String typename = ""; BookCaseDAO bookcaseDAO = new BookCaseDAO(); String str1 = null; Collection coll_bookcase = (Collection) bookcaseDAO.query(str1); if (coll_bookcase == null || coll_bookcase.isEmpty()) { out.println("<script>alert('请先录入书架信息!');history.back(-1);</script>"); } else { Iterator it_bookcase = coll_bookcase.iterator(); int bookcaseID = 0; String bookcasename = ""; PublishingDAO pubDAO = new PublishingDAO(); String str2 = null; Collection coll_pub = (Collection) pubDAO.query(str2); if (coll_pub == null || coll_pub.isEmpty()) { out.println("<script>alert('请先录入出版社信息!');history.back(-1);</script>"); } else { Iterator it_pub = coll_pub.iterator(); String isbn = ""; String pubname = ""; %> <script language="jscript"> function check(form){ if(form.barcode.value==""){ alert("请输入条形码!");form.barcode.focus();return false; } if(form.bookName.value==""){ alert("请输入图书名称!");form.bookName.focus();return false; } if(form.price.value==""){ alert("请输入图书定价!");form.price.focus();return false; } } </script>

这段代码是一个 JSP 页面，用于添加图书信息。在页面中，首先通过 BookTypeDAO、BookCaseDAO 和 PublishingDAO 查询图书类型、书架和出版社信息。如果这些信息为空，会通过 JavaScript 弹窗提示用户先录入相关信息。...

<%@ page language="java" import="java.util., java.sql." pageEncoding="utf-8"%> <%@page import="com.util.SQLConn"%> <%@page import="org.apache.commons.lang3.*" %> <%@page import="com.util.LOGS" %> <html> <body> <%-- 获取前端数据 --%> <% String username = request.getParameter("username"); String usernum = request.getParameter("usernum"); String name=request.getParameter("ytime"); String mon=request.getParameter("mtime"); String num=request.getParameter("rtime"); String people = request.getParameter("people"); %> <%-- 定义SQLConn类和INSERT_SQL常量 --%> <% final String INSERT_SQL = "INSERT INTO YuYue(UserID, Time, People) VALUES (?, ?, ?)"; %> <%-- 执行数据库操作 --%> <% int count = 0; try {Connection conn = SQLConn.openDB(); PreparedStatement pstmt = conn.prepareStatement(INSERT_SQL); { pstmt.setString(1, usernum); pstmt.setString(2, name+mon+num); pstmt.setString(3, people); count = pstmt.executeUpdate(); }} catch (SQLException e) { e.printStackTrace(); } %> <%-- 根据执行结果进行相应的操作 --%> <c:choose> <c:when test="${count > 0}"> <%-- 成功跳转到ZCS.jsp --%> <c:redirect url="ZCS.jsp"/> </c:when> <c:otherwise> <%-- 失败跳转到ZCB.jsp --%> <c:redirect url="../ZCB.jsp"/> </c:otherwise> </c:choose> </body> </html>优化代码

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <%@ page import="java.util.*, java.sql.*"%> <%@ page import="com.util.SQLConn"%> <%@ page import="com.util.LOGS"%...

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <%@ page import = "java.sql." %> <!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>数据处理页面</title> </head> <body> <% String userName = new String(request.getParameter("userName").getBytes("ISO-8859-1"),"UTF-8"); String password = new String(request.getParameter("password").getBytes("ISO-8859-1"),"UTF-8"); Statement st = null; Connection con = null; ResultSet rs = null; if(userName.equals("")){ response.sendRedirect("login.jsp"); } try{ Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver"); String url = "jdbc:sqlserver://localhost:1433;DatabaseName=eims;"; con = DriverManager.getConnection(url, "sa", "2017212027"); st = con.createStatement(); String sql = "select from sqlUser where userName = '"+userName+"'"; rs = st.executeQuery(sql); if(rs.next()){ String sql1 = "select * from sqlUser where password = '"+password+"'"; rs = st.executeQuery(sql1); if(rs.next()){ response.sendRedirect("main/main.jsp"); }else{ response.sendRedirect("login.jsp"); } } }catch(Exception e){ e.printStackTrace(); }finally{ rs.close(); st.close(); con.close(); } %> </body> </html>

然后使用JDBC连接到SQL Server数据库，查询用户表中是否存在该用户，查询结果保存在ResultSet对象中。如果存在该用户，继续查询该用户的密码是否匹配，并根据查询结果进行重定向。需要注意的是，该代码中存在一些...

<%@ page language="java" contentType="text/htm1; charset=GB1863日" pageEncoding="GB1893日" isThreadsafe="false™ import=" java.sql.,dp1. web., java.util.*"这是干什么的

其中，"contentType"指定了响应的MIME类型为"text/html"，"pageEncoding"指定了页面的字符编码格式为"GB1893日"，"isThreadsafe"指示页面是否是线程安全的，"import"用于导入需要使用的Java类和库，这里包括了SQL、...

以下代码为什么页面只能出现背景图片，不能出现用户名和密码的插入<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%> <%@ page import="java.sql.*" %> <!DOCTYPE html> <html> <head> <title>注册</title> </head> <body background="3.jpg" style=" background-repeat:no-repeat ; background-size:100% 100%; background-attachment: fixed;"> <% String username = request.getParameter("username"); String password = request.getParameter("password"); String confirm_password = request.getParameter("confirm_password"); Connection conn = null; PreparedStatement ps = null; try { Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver"); conn = DriverManager.getConnection("jdbc:sqlserver://127.0.0.1:1433;database=CJ;user=sa;password=Sa123456;encrypt=false;"); String sql = "insert into Admin2(username, password) values(?, ?)"; ps = conn.prepareStatement(sql); ps.setString(1, username); ps.setString(2, password); if (password.equals(confirm_password)) { ps.executeUpdate(); session.setAttribute("username", username); response.sendRedirect("main.jsp"); } else { out.println("两次密码不一致！"); } } catch (Exception e) { e.printStackTrace(); } finally { if (ps != null) { try { ps.close(); } catch (SQLException e) { e.printStackTrace(); } } if (conn != null) { try { conn.close(); } catch (SQLException e) { e.printStackTrace(); } } }%> </body> </html>

<input type="text" name="username" id="username"><br> <label for="password">密码：</label> <input type="password" name="password" id="password"><br> <label for="confirm_password">确认密码：</...

这个代码为什么报错<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8" %> <%@ page import="java.sql.*" %> <!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>修改密码</title> </head> <body> <% // 获取表单参数 String sno = request.getParameter("sno"); String oldPassword = request.getParameter("oldPassword"); String newPassword = request.getParameter("newPassword"); String confirmPassword = request.getParameter("confirmPassword"); // 验证新密码是否一致 if (!newPassword.equals(confirmPassword)) { out.println("新密码和确认密码不一致！"); return; } // 获取当前登录用户的信息 String sno = (String) session.getAttribute("sno"); try { // 创建数据库连接 Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver"); String url = "jdbc:sqlserver://127.0.0.1:1433;DatabaseName=CJ"; String username = "sa"; String password = "Sa123456"; Connection conn = DriverManager.getConnection(url, username, password); // 查询当前用户的密码 PreparedStatement pstmt = conn.prepareStatement("SELECT Password FROM Admin2 WHERE sno = ?"); pstmt.setString(1, sno); ResultSet rs = pstmt.executeQuery(); rs.next(); String dbPassword = rs.getString("Password"); // 验证原密码是否正确 if (!dbPassword.equals(oldPassword)) { out.println("原密码不正确！"); return; } // 更新用户密码 pstmt = conn.prepareStatement("update Admin2 set Password = ? WHERE sno = ?"); pstmt.setString(1, newPassword); pstmt.setString(2, sno); pstmt.executeUpdate(); out.println("密码修改成功！"); // 关闭数据库连接 rs.close(); pstmt.close(); conn.close(); } catch (Exception e) { out.println("数据库操作出现异常：" + e.getMessage()); } %> </body> </html>

<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8" %> <%@ page import="java.sql.*" %> <!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>修改密码</title> ...

JSP页面指令详解：包括 <%@page %> 标签的作用与注意事项

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8" contentType="text/html; charset=UTF-8" %> - language属性：指定使用的脚本语言，这里是"java"，表示使用Java作为脚本语言。 - ...

<%@ page language- 'java" import= "java.util.,_ 1_ .jvax.sql. " contentType-" text/html;charset=GBK"%><html> <body> <%Connection con-null; 2)_st=null; int counter=0; Savepoint p=null,p0= null,p1=null; try { Class.forName("com._ 3)_ .cj.jdbc.Driver"); String url= "jdbc:mาysq.:/lcalhost3306/student?_ 4_ =Asia/Shanghai&user-root&password-123456"con=DriverManager._ (5)_ (url); String sql="insert into student(id,username, chinesecent,mathcent) value(?,?,?,?)"; st=con.prepareStatement(_ _6)_ ); con. setAutoCommit{_ 7_ _); p0=con.setSavepoint("1"); counter=1; st.setString(1."777"); st.setString(2."Wang"); st. setFloat(3,"85"); st.setFloat(4,"90");. st.executeUpdate(); p1-con.setSavepoint("2"); counter-=2; st. setstrin(.112233445566777"); st. setString(2,"Zhang"); st. setFloat(3,"80"); st. .setFloat(4,"85 '); st.executeUpdate(); con._ _(8_ ();. out. println("成功加入成绩记录，请验证"); } catch(Exception e out.println("出错： "+e); out. println("
回滚事务"); switch(counter) { case 1: con.rollback(_ 9_ ); break; case 2: con.rollback(p1); break; default: con.rollback(); } } finally { if(st!=null) st.close(); } if(con!=null) { con.setAutoCommit(true); con.close(); } } </body> </html> 阅读上述带事务处理的JDBC编程程序，分析程序最终执行的结果是成功加入（10）条学生记录，请补充填写1-10处内容

6. 应该填写sql 7. 应该填写false 8. 应该填写commit() 9. 应该填写p0 10. 成功加入2条学生记录。程序执行时，第一条记录成功插入，第二条记录插入时出错，触发了异常，执行了回滚操作，因此只有第一条记录...

请修改下面的两段代码使之能运行，代码 1<body> <%request.setCharacterEncoding("utf-8");//解决提交乱码问题 %> <% String stuno = request.getParameter("stuno"); String stuname = request.getParameter("stuname"); if (stuno != null) { Class.forName("com.mysql.cj.jdbc.Driver"); Connection conn = DriverManager.getConnection("jdbc:mysql: //127.0.0.1:3306/sys", "root", "1234"); PreparedStatement ps = null; ResultSet rs = null; String sql = "SELECT num FROM tb_student WHERE NUM=?"; ps = conn.prepareStatement(sql); ps.setString(1, stuno); rs = ps.executeQuery(); if (rs.next()) { out.println("对不起，该学生学号已经存在！"); } else { sql = "INSERT INTO tb_student(NUM,NAME) VALUES(?,?)"; ps = conn.prepareStatement(sql); ps.setString(1, stuno); ps.executeUpdate(); out.println("添加成功！"); } } %> 添加学生信息
<form method="post"> 输入学号:<input type="text" name="stuno">
输入姓名:<input type="text" name="stuname">
<input type="submit" value="添加"> </form> </body> </html>，代码2 // 添加学生信息到数据中 public int addStudent(Student student) throws Exception { initConnection(); // 创建一个sql语句 String sql = "insert into tb_student(num,name) values (?,?)"; // 创建一个PreparedStatement对象 PreparedStatement ps = conn.prepareStatement(sql); // 填充参数 ps.setString(1, student.getNum()); ps.setString(2, student.getName()); // 执行sql语句 int retv = ps.executeUpdate(); ps.close(); // 关闭链接 closeConnection(); return retv; }

<%@ page import="java.sql.*" %> <!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>添加学生信息</title> </head> <body> <% request.setCharacterEncoding("utf-8");//解决提交乱码问题 String ...

JAVA-JSP学习笔记.doc

5. **设置中文支持**：为解决中文乱码问题，需要在JSP页面头部添加<%@ page contentType="text/html;charset=UTF-8"%>来设定字符编码。 6. **引入文件**：使用<%@ include file="xxx.jsp"%>可以将一个JSP文件...

编写程序,实现对数据库StudentInfo中的表student进行插入操作.要求使用预处理语句对象PreparedStatement完成以下数据的插入: insert into student values('001','张三',18,'女') 注:给定数据库登录用户名:sa,密码:123. Input.jsp: 请输入待新增的学生信息学号: 姓名: 年龄: 性别: addStudent.jsp: <% String url="jdbc:sqlserver://localhost;databaseName=StudentInfo"; request.setCharacterEncoding("utf-8"); String sno = request.getParameter("sno"); String sname = request.getParameter("sname"); int sage = Integer.valueOf(request.getParameter("sage")); String sex = request.getParameter("sex"); try{ //补全此部分代码 } // 捕获异常 catch(SQLException ex) { System.out.println ("\n* 发生SQL异常 *\n"+ex.getMessage()); } catch(ClassNotFoundException ex) { System.out.println(ex); }

<%@ page import="java.sql.*" %> <!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>Insert Student</title> </head> <body> <% String url="jdbc:sqlserver://localhost;databaseName=StudentInfo"; ...

商品Id:<input type="text" name="pid" placeholder="商品ID可以不输入"> 前端输入商品ID后通过数据库product表精确查询，将查询到的商品id、商品图片、商品价格展示在前端jsp页面的代码

<%@ page import="java.sql.*" %> <%@ page import="com.example.Product" %> <!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>商品查询结果</title> </head> <body> <h1>商品查询结果</h1> <% ...

<input type="number" id="quantity" name="quantity" min="1" max="10" value="1"> <button class="add-to-cart" data-product-id="0001" data-product-quantity="quantity">加入购物车</button>如何获取数量点击后用jsp获取ID和数量值

<%@ page import="java.io.*,java.util.*,java.sql.*"%> <% // 获取表单提交的商品ID和数量值 String productId = request.getParameter("productId"); String quantity = request.getParameter("quantity"); ...

相关推荐

基于Java的制作简单的表单程序（Jsp）.zip

Java Web应用开发：展示全部商品.docx

java学生课绩管理系统jsp+servlet+javaBean+sqlserver

讲解<%@ page contentType="text/html; charset=utf-8" language="java" import="java.sql." errorPage=""%> <%@ page import="com.dao.BookDAO"%> <%@ page import="com.actionForm.BookForm"%> <%@ page import="java.util."%> <html> <% Collection coll = (Collection) req

<%@ page language="java" contentType="text/htm1; charset=GB1863日" pageEncoding="GB1893日" isThreadsafe="false™ import=" java.sql.*,dp1. web.*, java.util.*"这是干什么的

JSP页面指令详解：包括 <%@page %> 标签的作用与注意事项

JAVA-JSP学习笔记.doc

商品Id:<input type="text" name="pid" placeholder="商品ID可以不输入"> 前端输入商品ID后通过数据库product表精确查询，将查询到的商品id、商品图片、商品价格展示在前端jsp页面的代码

<input type="number" id="quantity" name="quantity" min="1" max="10" value="1"> <button class="add-to-cart" data-product-id="0001" data-product-quantity="quantity">加入购物车</button>如何获取数量点击后用jsp获取ID和数量值

最新推荐

PaddleTS 是一个易用的深度时序建模的Python库，它基于飞桨深度学习框架PaddlePaddle，专注业界领先的深度模型，旨在为领域专家和行业用户提供可扩展的时序建模能力和便捷易用的用户体验

白色大气风格的乐器爱好者网站模板下载.zip

RStudio中集成Connections包以优化数据库连接管理

管理建模和仿真的文件

Keil uVision5全面精通指南

flink提交给yarn19个全量同步MYsqlCDC的作业，flink的配置参数怎样设置

PHP博客旅游的探索之旅

"互动学习：行动中的多样性与论文攻读经历"

【单片机编程实战】：掌握流水灯与音乐盒同步控制的高级技巧

java 号码后四位用‘xxxx’脱敏

<%@ page language="java" contentType="text/htm1; charset=GB1863日" pageEncoding="GB1893日" isThreadsafe="false™ import=" java.sql.,dp1. web., java.util.*"这是干什么的