【web应用系统实践】第四章作业

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代码可以自由复制、转载。

建立数据库 lianxi，在该数据库下建立一个图书表 book，图书包含信息：图书号、图书名、作者、价格、备注字段。设计一应用程序，完成图书信息的管理。主要完成图书信息的添加、查询、删除、修改等操作。

(1个数据库建表语句 + 1个Java类 + 5个页面 )

1. 数据库建表语句

create database if not exists lianxi;
use lianxi;
drop table if exists book;
create table book(
    id       int auto_increment primary key,
    bookName varchar(30)  default ''   not null,
    author   varchar(20)  default ''   not null,
    price    float(8, 2)  default 0.00 not null,
    message  varchar(100) default ''   not null
);

INSERT INTO lianxi.book ( bookName, author, price, message) VALUES ( '《作业好难》', 'yourself', 30, '做完了吗？');

2. DBBean.java（数据库连接类）

package book.bean;
import java.sql.*;
public class DBBean {
    
    
    private String driverStr="com.mysql.cj.jdbc.Driver";
    private String url1="jdbc:mysql://localhost:3306/lianxi";
    private String url2="?user=root&password=123456";
    private String url3="&useUnicode=true&characterEncoding=UTF-8";
    private String connStr;
    private Connection conn=null;
    private Statement stmt=null;
    public DBBean(){
    
    
        connStr=url1+url2+url3;
        try{
    
    
            Class.forName(driverStr);
            conn = DriverManager.getConnection(connStr);
            stmt = conn.createStatement();
        }catch(Exception ex){
    
    
            System.out.println("无法同数据库建立连接！");
        }
    }
    public int executeUpdate(String s){
    
    
        int result=0;
        try{
    
    
            result=stmt.executeUpdate(s);
        }catch(Exception ex){
    
    
            System.out.println("执行更新错误！");
        }
        return result;
    }
    public ResultSet executeQuery(String s){
    
    
        ResultSet rs=null;
        try{
    
    
            rs=stmt.executeQuery(s);
        }
        catch(Exception ex){
    
    
            System.out.println("执行查询错误！");
        }
        return rs;
    }
    public void close(){
    
    
        try{
    
    
            stmt.close();
            conn.close();
        }
        catch(Exception e){
    
    }
    }
}

3. index.jsp（首页）

<%@ page import="java.sql.*" pageEncoding="UTF-8" %>
<html>
<head>
    <title>图书系统</title>
</head>
<body>
<center><a href=addBook.jsp>增加图书信息</a></center>
<p>
<table align=center width=510 border=1.5>
    <tr>
        <td>书名
        <td>作者
        <td>价格
        <td>操作
        <td>备注
            <jsp:useBean id="db" class="book.bean.DBBean"/>
                <%
	  String s="select * from book";
	  ResultSet resultSet=db.executeQuery(s);
	  while(resultSet.next()){
	    int id=resultSet.getInt(1);
	    out.println("<tr><td>"+resultSet.getString(2)+"</td><td>"+resultSet.getString(3)+"</td><td>"+resultSet.getString(4)+"</td><td><a href='dropBook.jsp?id="+id+"'>删除</a>&nbsp;<a href='editBook.jsp?id="+id+"'>修改</a></td><td>"+resultSet.getString(5)+"</td></tr>");
	  }
	  resultSet.close();
	  db.close();
	  %>
</table>
</body>
</html>

4. addBook.jsp（添加图书页面）

<%@ page contentType="text/html; charset=gb2312"  %>
<html>
<head><title>添加图书</title></head>
<body>
<form action="addBook.jsp" method="post">
    <table width="50%" border="1" align="center">
        <CAPTION>添加图书</CAPTION>
        <tr>
            <th width="40%">书名：</th>
            <td width="60%"><input name="bookName" type="text"></td>
        </tr>
        <tr>
            <th>作者：</th>
            <td><input name="author" type="text"></td>
        </tr>
        <tr>
            <th>价格：</th>
            <td><input name="price" type="text">&nbsp;元</td>
        </tr>
        <tr>
            <th>备注：</th>
            <td><input name="message" type="text"></td>
        </tr>
        <tr>
            <th colspan="2">
                <input type="submit" name="submit" value="提交">
                <input type="reset" value="重置">
            </th>
        </tr>
    </table>
</form>

<jsp:useBean id="db" class="book.bean.DBBean"/>
<%
    request.setCharacterEncoding("gb2312");
    String submit = request.getParameter("submit");
    if (submit != null && !submit.equals("")) {
        String b = request.getParameter("bookName");
        String m  = request.getParameter("message");
        String p    = request.getParameter("price");
        String a   = request.getParameter("author");
        String sql      = "insert into book(bookName,author,price,message) values('" + b + "','" + a + "'," + p + ",'" + m + "')";
        int    i        = db.executeUpdate(sql);
        if (i == 1) {
            out.println("<script language='javaScript'> alert('添加成功!');</script>");
            response.setHeader("refresh", "1;url=index.jsp");
        } else {
            out.println("<script language='javaScript'> alert('添加失败，请重试！');</script>");
            response.setHeader("refresh", "1;url=addBook.jsp");
        }
        db.close();
    }
%>
</body>
</html>

5. editBook.jsp（编辑图书页面）

<%@ page import="java.sql.*" pageEncoding="gb2312" %>
<html>
<head><title>修改图书</title></head>
<body>
<jsp:useBean id="db" class="book.bean.DBBean" />
<%
  request.setCharacterEncoding("gb2312");
  String id=request.getParameter("id");
  ResultSet resultSet =db.executeQuery("select * from book where id="+id);
  resultSet.next();
%>
<form action="update.jsp" method="post">
  <table width="60%" border="1" align="center">
    <CAPTION>修改图书</CAPTION>
    <tr>
      <th width="40%">书名：</th>
      <td width="60%">
        <input name="bookName" type="text" value="<%=resultSet.getString(2)%>"></td>
    </tr>
    <tr>
      <th>作者：</th>
      <td><input name="author" type="text" value="<%=resultSet.getString(3)%>"></td>
    </tr>
    <tr>
      <th>价格：</th>
      <td><input name="price" type="text" value="<%=resultSet.getString(4)%>">元</td>
    </tr>
    <tr>
      <th>备注：</th>
      <td><input name="message" type="text" value="<%=resultSet.getString(5)%>"></td>
    </tr>
    <tr>
      <th colspan="2">
        <input type="hidden" name="id" value="<%=id%>">
        <input type="submit" value="提交">
        <input type="reset" value="重置">
      </th>
    </tr>
  </table>
</form>
<%
  db.close();
%>
</body>
</html>

6. update.jsp（更新操作）

<%@ page  contentType="text/html; charset=gb2312" %>
<html>
<head>
    <title>update</title>
</head>
<body>
<jsp:useBean id="db" class="book.bean.DBBean"/>
<%
    request.setCharacterEncoding("gb2312");
    String b = request.getParameter("bookName");
    String a = request.getParameter("author");
    String p = request.getParameter("price");
    String id = request.getParameter("id");
    String m = request.getParameter("message");
    String sql = "update book set bookName='" + b + "',author='" + a + "',price=" + p + ",message='" + m + "' where id=" + id;
    int i = db.executeUpdate(sql);
    if (i == 1) {
        out.println("<script language='javaScript'> alert('修改成功！');</script>");
        response.setHeader("refresh", "1;url=index.jsp");
    }
    db.close();
%>
</body>
</html>

7. dropBook.jsp（删除图书操作）

<%@ page contentType="text/html; charset=gb2312" %>
<html>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<head><title>删除</title></head>
<body>
<jsp:useBean id="db" class="book.bean.DBBean"/>
<%
  String id=request.getParameter("id");
  request.setCharacterEncoding("gb2312");
  int i=db.executeUpdate("delete from book where id="+id);
  if(i==1)
  {out.println("<script language='javaScript'> alert('删除成功！');</script>");
    response.setHeader("refresh","1;url=index.jsp");
  }
  else{
    out.println("<script language='javaScript'> alert('删除失败！');</script>");
    response.setHeader("refresh","1;url=dropBook.jsp");
  }
  db.close();
%>
</body>
</html>

（结束）

设计一个简单的网上名片管理系统，实现名片的增、删、改、查等操作。该名片管理系统包括如下功能。

(1) 用户登录与注册

用户登录：在登录时，如果用户名和密码正确，进入系统页面。

用户注册：新用户应该先注册，然后再登录该系统。

(2) 名片管理

增加名片：以仿真形式（按常用的名片格式）增加名片信息。

修改名片：以仿真形式（按常用的名片格式）修改名片信息。

查询名片：以模糊查询的方式查询名片。

删除名片：名片的删除有两种方式，即把名片移到回收站，把名片彻底删除。

(3) 回收站管理

还原：把回收站中的名片还原回收。

彻底删除：把名片彻底从回收站删除。

浏览/查询：可以模糊查询、浏览回收站中的名片。

在这里插入图片描述

(1个数据库建表语句 + 1个Java类 + 10个页面 )

1. 数据库建表语句

create database if not exists lianxi;
use lianxi;
drop table if exists user;
create table user(
                     id int primary key auto_increment,
                     username varchar(30) not null unique ,
                     password varchar(30) not null default '123456'
                         comment '默认密码都是123456'
);

# 管理员账号admin，密码123456
insert into user(username, password) values ('admin','123456');

drop table if exists card;
create table card(
                     id int primary key auto_increment,
                     name varchar(50) not null ,
                     age int,
                     sex char(1),
                     work varchar(50),
                     logicDelete int default 0
);
insert into card( name, age, sex, work) values ('张三',22,'男','职员'),
                                               ('李四',20,'女','经理');

2. DBBean.java（数据库连接类）

package book.bean;
import java.sql.*;
public class DBBean {
    
    
    private String driverStr="com.mysql.cj.jdbc.Driver";
    private String url1="jdbc:mysql://localhost:3306/lianxi";
    private String url2="?user=root&password=123456";
    private String url3="&useUnicode=true&characterEncoding=UTF-8";
    private String connStr;
    private Connection conn=null;
    private Statement stmt=null;
    public DBBean(){
    
    
        connStr=url1+url2+url3;
        try{
    
    
            Class.forName(driverStr);
            conn = DriverManager.getConnection(connStr);
            stmt = conn.createStatement();
        }catch(Exception ex){
    
    
            System.out.println("无法同数据库建立连接！");
        }
    }
    public int executeUpdate(String s){
    
    
        int result=0;
        try{
    
    
            result=stmt.executeUpdate(s);
        }catch(Exception ex){
    
    
            System.out.println("执行更新错误！");
        }
        return result;
    }
    public ResultSet executeQuery(String s){
    
    
        ResultSet rs=null;
        try{
    
    
            rs=stmt.executeQuery(s);
        }
        catch(Exception ex){
    
    
            System.out.println("执行查询错误！");
        }
        return rs;
    }
    public void close(){
    
    
        try{
    
    
            stmt.close();
            conn.close();
        }
        catch(Exception e){
    
    }
    }
}

3. index.jsp（首页、登录页面）

<%@ page import="java.sql.*" %>
<%@ page contentType="text/html;charset=UTF-8" %>
<html>
<head>
    <title>名片管理系统</title>
    <style>
        p {
      
      
            text-align: center;
            margin: 5px;
        }
        * {
      
      
            margin: 0;
            padding: 0;
        }
        div {
      
      
            text-align: center;
        }
        .custom {
      
      
            display: flex;
            justify-content: center;
            align-items: center;
            width: 400px;
            height: 400px;
            margin: 150px auto;
            border: 1px solid red;
        }
    </style>
</head>
<body>
<div class="custom">
    <form action="index.jsp">
        <p>用户名：<input type="text" name="username"></p>
        <p>密码&emsp;：<input type="password" name="password" ></p>
        <br>
        <input type="submit" name="submit" value="登录" style="font-size: 16px;padding: 5px 5px;margin: 5px">
        <br>
        <a href="register.jsp">没有账号，立即注册？</a>
    </form>
    </form>
</div>

<jsp:useBean id="db" class="book.bean.DBBean"/>
<%
    request.setCharacterEncoding("gb2312");
    String submit = request.getParameter("submit");
    if (submit != null && !submit.equals("")) {
        String    username = request.getParameter("username");
        String    password = request.getParameter("password");
        String    sql      = "select count(*) from user where username = '" + username + "' and password = '" + password + "'";
        ResultSet rs       = db.executeQuery(sql);
        int       count    = 0;
        // 判断是否登录
        if (rs.next()) {
            count = rs.getInt(1);
        }
        if (count == 1) {
            Cookie cookie = new Cookie("login", username);
            response.addCookie(cookie);
            Cookie cookie2 = new Cookie("key", "");
            response.addCookie(cookie2);
            response.setHeader("refresh", "1;url=card.jsp");

        } else {
            out.println("<script language='javaScript'> alert('账号或密码错误！');</script>");
            response.setHeader("refresh", "1;url=index.jsp");
        }
        db.close();
    } %>
</body>
</html>

4. register.jsp（注册页面）

<%@ page import="java.sql.*" %>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>注册</title>
    <style>
        * {
      
      
            margin: 0;
            padding: 0;
        }
        p {
      
      
            text-align: center;
            margin: 5px;
        }
        div {
      
      
            text-align: center;
        }
        .custom {
      
      
            display: flex;
            justify-content: center;
            align-items: center;
            width: 300px;
            height: 300px;
            margin: 150px auto;
            border: 1px solid red;
        }
    </style>
</head>
<body>
<div class="custom">
    <form action="register.jsp">
        <p>用户名：<input type="text" name="username"></p>
        <p>密码&emsp;：<input type="password" name="password" ></p>
        <br>
        <input type="submit" name="submit" value="注册账号" style="font-size: 18px;padding: 3px 3px;margin: 3px">
        <br>
    </form>
    </form>
</div>

<jsp:useBean id="db" class="book.bean.DBBean" />
<%
    request.setCharacterEncoding("gb2312");
    String submit = request.getParameter("submit");
    if (submit != null && !submit.equals("")) {
        String u = request.getParameter("username");
        String p = request.getParameter("password");
        String s      = "insert into user(username,password) values('" + u + "','" + p + "')";
        try {
            int n = db.executeUpdate(s);
            if (n > 0) {
                out.println("<script language='javaScript'> alert('注册成功！');</script>");
                response.setHeader("refresh", "1;url=index.jsp");
            } else {
                out.println("<script language='javaScript'> alert('账号已存在，请重新输入！');</script>");
                response.setHeader("refresh", "1;url=register.jsp");
            }
        } catch (Exception e) {
            out.println("<script language='javaScript'> alert('未知错误！');</script>");
            response.setHeader("refresh", "1;url=index.jsp");
        }
        db.close();
    }
%>
</body>
</html>

5. card.jsp（名片页面）

<%@ page import="java.sql.*" %>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>名片管理系统</title>
    <style>
        .center {
      
      
            display: block;
            text-align: center;
        }
    </style>
</head>
<body>
<%
    // 获取所有的cookie
    Cookie[] cookies = request.getCookies();
    String key = "";
    for (int i = 0; i < cookies.length; i++) {
        if (cookies[i].getName().equals("login")) {
            out.println("<h1 class=\"center\">欢迎你，" + cookies[i].getValue() + "！</h1>");
        }
        if (cookies[i].getName().equals("key")) {
            key = cookies[i].getValue();
        }
    }
%>
<div class="center">
    <a href=addCard.jsp>添加名片</a>
    &emsp;&emsp;<a href=cycleCard.jsp>回收站</a>
    &emsp;&emsp;<a href=index.jsp>退出登录</a>
</div>
<form class="center">
    姓名：<input type="text" name="key" >
    <input type="button" value="查找" onclick="seek()">
</form>
<table align=center width=500 border=1>
    <tr>
        <td>姓名
        <td>年龄
        <td>性别
        <td>职位
        <td>操作
            <jsp:useBean id="db" class="book.bean.DBBean" />
                <%
	  String s="select * from card where logicDelete=0 and name like '%"+key+"%'";
	  ResultSet rs=db.executeQuery(s);
	  while(rs.next()){
	    int id=rs.getInt(1);
	    out.println("<tr><td>"+rs.getString(2)+"</td><td>"+rs.getString(3)+"</td><td>"+rs.getString(4)+"</td><td>"+rs.getString(5)+"<td><a href='delCard.jsp?id="+id+"'>删除</a>&nbsp;<a href='editCard.jsp?id="+id+"'>修改</a></td></tr>");
	  }
	  rs.close();
	  db.close();
	  %>
</table>
<script>
    function seek(){
      
      
        var key = document.forms[0].key.value;
        document.cookie = " key =  "+key;
        document.forms[0].submit()
    }
</script>
</body>
</html>

6. addCard.jsp（添加名片页面）

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>添加名片</title>
    <style>
        div {
      
      
            text-align: center;
        }

        .custom {
      
      
            display: flex;
            align-items: center;
            width: 500px;
            height: 300px;
            margin: 150px auto;
            border: 1px solid green;
            padding: 3px;
        }

        .img {
      
      
            margin-left: 150px;
            border: 1px solid green;
            width: 100px;
            height: 150px;
            ine-height: 150px;
            text-align: center;
            font-size: 16px;
        }
    </style>
</head>
<body>
<a href="card.jsp" style="display: block;text-align: center;font-size: 24px">返回首页</a>
<div class="custom">
    <form action="addCard.jsp">
        <p>姓名：<input type="text" name="name">
        <p>年龄：<input type="number" name="age"></p>
        <p>性别：<input type="radio" name="sex" value="男" checked>男&emsp;
            <input type="radio" name="sex" value="女">女</p>
        <p>职位：<input type="text" name="work"></p>
        <br>
        <input type="submit" name="submit" value="添加" style="font-size: 16px;padding: 3px 3px;margin: 3px">
        <br>
    </form>
    </form><span class="img">这是头像</span>
</div>
</body>
<jsp:useBean id="db" class="book.bean.DBBean" scope="page"/>
<%
    request.setCharacterEncoding("gb2312");
    String submit = request.getParameter("submit");
    if (submit != null && !submit.equals("")) {
        String n = request.getParameter("name");
        String a   = request.getParameter("age");
        String s    = request.getParameter("sex");
        String w  = request.getParameter("work");
        String sql      = "insert into card(name,age,sex,work) values('" + n + "'," + a + ",'" + s + "','" + w + "')";
        int    i        = db.executeUpdate(sql);
        if (i == 1) {
            out.println("<script language='javaScript'> alert('添加成功！');</script>");
            response.setHeader("refresh", "1;url=addCard.jsp");
        } else {
            out.println("<script language='javaScript'> alert('添加失败！');</script>");
            response.setHeader("refresh", "1;url=addCard.jsp");
        }
        db.close();
    }
%>
</html>

7. editCard.jsp（名片编辑页面）

<%@ page import="java.sql.*" %>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
    <style>
        div {
      
      
            text-align: center;
        }
        .custom {
      
      
            display: flex;
            align-items: center;
            width: 500px;
            height: 300px;
            margin: 150px auto;
            border: 1px solid green;
            padding: 3px;
        }

        .img {
      
      
            margin-left: 150px;
            border: 1px solid green;
            width: 100px;
            height: 150px;
            ine-height: 150px;
            text-align: center;
        }
    </style>
</head>
<body>
<jsp:useBean id="db" class="book.bean.DBBean" />
<%
    request.setCharacterEncoding("gb2312");
    String id=request.getParameter("id");
    ResultSet resultSet =db.executeQuery("select * from card where id="+id);
    resultSet.next();
%>
<a href="card.jsp" style="display: block;text-align: center;font-size: 24px">返回首页</a>
<div class="custom">
    <form action="updateCard.jsp">
        <p>姓名：<input type="text" name="name" value="<%=resultSet.getString(2)%>">
        <p>年龄：<input type="number" name="age" value="<%=resultSet.getString(3)%>"></p>
        <p>性别：<input type="radio" name="sex" value="男" checked>男&emsp;
            <input type="radio" name="sex" value="女">女</p>
        <p>职位：<input type="text" name="work" value="<%=resultSet.getString(5)%>"></p>
        <br>
        <input type="hidden" name="id" value="<%=id%>">
        <input type="submit" name="submit" value="确定修改" style="font-size: 16px;padding: 5px 5px;margin: 5px">
        <br>
    </form><span class="img">这是头像</span>
</div>
</body>
</html>

8. updateCard.jsp（名片更新操作）

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>update</title>
</head>
<body>
<jsp:useBean id="db" class="book.bean.DBBean" />
<%
    request.setCharacterEncoding("gb2312");
    String n = request.getParameter("name");
    String a = request.getParameter("age");
    String s = request.getParameter("sex");
    String w = request.getParameter("work");
    String id = request.getParameter("id");
    String sql = "update card set name='" + n + "',age=" + a + ",sex='" + s + "',work ='"+ w +"' where id=" + id;
    int i = db.executeUpdate(sql);
    if (i == 1) {
        out.println("<script language='javaScript'> alert('修改成功！');</script>");
        response.setHeader("refresh", "1;url=card.jsp");
    }
    db.close();
%>
</body>
</html>

9. delCard.jsp（删除名片，逻辑删除）

<%@ page contentType="text/html; charset=gb2312" language="java" import="java.sql.*"%>
<html>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<head><title>delete</title></head>
<body>
<jsp:useBean id="db" class="book.bean.DBBean"/>
<%
    request.setCharacterEncoding("gb2312");
    String id=request.getParameter("id");
    int i=db.executeUpdate("update card set logicDelete = 1 where id="+id);
    if(i==1)
    {out.println("<script language='javaScript'> alert('删除成功！');</script>");
        response.setHeader("refresh","1;url=card.jsp");
    }
    else{
        out.println("<script language='javaScript'> alert('删除失败！');</script>");
        response.setHeader("refresh","1;url=card.jsp");
    }
    db.close();
%>
</body>
</html>

10. cycleCard.jsp（名片回收站）

<%@ page import="java.sql.*" %>
<%@ page import="com.sun.jdi.*" %>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>回收站</title>
    <style>
        .center {
      
      
            display: block;
            text-align: center;
        }
    </style>
</head>
<body>
<div class="center">
    <a href=card.jsp>返回首页</a>
    <form  class="center">
        关键词：<input type="text" name="key">
        <input type="button" value="搜索" onclick="seek()">
    </form>
    <table align=center width=500 border=1>
        <tr>
            <td>姓名
            <td>年龄
            <td>性别
            <td>职位
            <td>操作
                <jsp:useBean id="db" class="book.bean.DBBean"/>
                    <%
                     String key = "";
                      Cookie[] cookies = request.getCookies();
                     for (int i = 0; i < cookies.length; i++) {
        if (cookies[i].getName().equals("key2")) {
            key = cookies[i].getValue();
        }
    }
	  String s="select * from card where logicDelete=1 and name like '%"+key+"%'";
	  ResultSet rs=db.executeQuery(s);
	  while(rs.next()){
	    int id=rs.getInt(1);
	    out.println("<tr><td>"+rs.getString(2)+"</td><td>"+rs.getString(3)+"</td><td>"+rs.getString(4)+"</td><td>"+rs.getString(5)+"<td><a href='recoverCard.jsp?id="+id+"'>恢复</a>&emsp;"+"<a href='dropCard.jsp?id="+id+"'>彻底删除</a></td></tr>");
	  }
	  rs.close();
	  db.close();
	  %>
    </table>
</div>
<script>
    function seek() {
      
      
        var key = document.forms[0].key.value;
        document.cookie = " key2 =  " + key;
        location.reload()
    }
</script>
</body>
</html>

11. recoverCard.jsp（恢复操作）

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
<jsp:useBean id="db" class="book.bean.DBBean" />
<%
    request.setCharacterEncoding("gb2312");
    String id=request.getParameter("id");
    int i=db.executeUpdate("update card set logicDelete = 0 where id="+id);
    if(i==1)
    {out.println("<script language='javaScript'> alert('恢复成功！');</script>");
        response.setHeader("refresh","1;url=cycleCard.jsp");
    }
    else{
        out.println("<script language='javaScript'> alert('恢复成功！');</script>");
        response.setHeader("refresh","1;url=cycleCard.jsp");
    }
    db.close();
%>
</body>
</html>

12. dropCard.jsp（彻底删除名片，物理删除）

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
  <title>drop</title>
</head>
<body>
<jsp:useBean id="db" class="book.bean.DBBean"/>
<%
  request.setCharacterEncoding("gb2312");
  String id=request.getParameter("id");
  int i=db.executeUpdate("delete from card where id="+id);
  if(i==1)
  {out.println("<script language='javaScript'> alert('删除成功！');</script>");
    response.setHeader("refresh","1;url=cycleCard.jsp");
  }
  else{
    out.println("<script language='javaScript'> alert('删除失败！');</script>");
    response.setHeader("refresh","1;url=cycleCard.jsp");
  }
  db.close();
%>
</body>
</html>