動態生成頁面（從資料庫中動態取出資料資訊生成頁面）
阿新 • • 發佈：2019-02-04
做課程設計的時候 做的有點煩了 所以就簡單的寫了點 以下就是將新增到購物車的商品動態的顯示到前臺頁面的程式碼
首先是我的head.jsp這裡面的“我的目錄“使用的不是直接連結而是一個servlet名稱叫做”selectUserCart“
我的裡面使用的user、books、userAccout類都是基本的記錄了基本資訊的類為其實現setXxx（）和getXxx（）方法
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%> <% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <link rel="stylesheet" type="text/css" href="style.css" /> </head> <body > <div id="wrap" > <% if(session.getAttribute("username") == null) { %> <br/>你還沒有登入請<a href="login.jsp">登陸</a>/<a href="register.jsp">註冊</a>以檢視或購買 <% }else{ %> <br/>您好！<%=session.getAttribute("username") %> <% } %> <div class="header"> <!-- <br/>你還沒有登入請<a href="login.jsp">登陸</a>/<a href="register.jsp">註冊</a>以檢視或購買 --> <div class="logo"><a href="index.htm"><img src="images/logo.gif" alt="" title="" border="0" /></a></div> <div id="menu"> <ul> <li class="selected"><a href="index.jsp">主頁</a></li> <li><a href="about.jsp">關於我們</a></li> <li><a href="category">圖書</a></li> <li><a href="specials.jsp">特別推薦</a></li> <li><a href="selectUserCart">我的目錄</a></li> <li><a href="register.jsp">註冊</a></li> <li><a href="contact.jsp">購買</a></li> </ul> </div> </div> </div> </body> </html>
然後是我使用到的兩個類：搜尋我的購物車的工具類：myCartUtil.java<pre name="code" class="java">package myCart; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import bookConnUtil.DBUtil; import bookConnUtil.books; public class myCartUtil { public static ArrayList<mycart> list = new ArrayList<mycart>(); public static ArrayList<books> booklist = new ArrayList<books>(); public static String msg; public static int countbook = 0; //public static mycart[] cart = new mycart[10]; public static int count = 0; public static boolean insertIntoMyCart(String username,String bookname,String pianduanName) throws SQLException{ String cartInsert = "insert into userAccount valus(?,?,?)"; boolean flag = false; Connection conn=null; PreparedStatement stmt=null; try{ conn = DBUtil.getConnection(DBUtil.CONNECTION_SQL); stmt = conn.prepareStatement(cartInsert); stmt.setString(1, username); stmt.setString(2, bookname); stmt.setString(3, pianduanName); int count = stmt.executeUpdate(); if(count>0){ flag=true; }else{ flag=false; } }catch(Exception e){ System.out.println("真心對不住，您的程式出錯了"); e.printStackTrace(); }finally{ conn.close(); stmt.close(); } return flag; } public static boolean selectUserCart(String userName) throws SQLException{ boolean flag = false; String cartSelect = "select username,bookname,pianduanName,imagePath,price from userAccount where username =?"; Connection conn=null; ResultSet rs=null; PreparedStatement stmt=null; try{ conn = DBUtil.getConnection(DBUtil.CONNECTION_SQL); stmt = conn.prepareStatement(cartSelect); stmt.setString(1, userName); rs = stmt.executeQuery(); while(rs.next()){ mycart cart = new mycart(); cart.setUserName(rs.getString(1)); cart.setBookName(rs.getString(2)); cart.setPianduanName(rs.getString(3)); cart.setImagePath(rs.getString(4)); cart.setPrice(rs.getInt(5)); list.add(cart); count++; } System.out.println("++++++++++++++++"+count+"+++++++++++++"); if(count==0){ msg = "null"; }else{ msg = "full"; } flag = true; }catch(Exception e){ System.out.println("真心對不起，你的程式出錯了"); e.printStackTrace(); }finally{ conn.close(); stmt.close(); } return flag ; } public static boolean selectAllBooks() throws SQLException{ boolean flag = false; String cartSelect = "select bookId,bookName,pianduanName,imagesPath,price from books"; Connection conn=null; ResultSet rs=null; PreparedStatement stmt=null; try{ conn = DBUtil.getConnection(DBUtil.CONNECTION_SQL); stmt = conn.prepareStatement(cartSelect); rs = stmt.executeQuery(); while(rs.next()){ books book = new books(); book.setBookID(rs.getString(1)); book.setBookName(rs.getString(2)); book.setPianduanName(rs.getString(3)); book.setImagePath(rs.getString(4)); book.setPrice(rs.getInt(5)); booklist.add(book);
<span style="white-space:pre"> </span>//我沒怎麼好好做所以就用這個標記的 想要做的更好點請自行實現 countbook++; } System.out.println("++++++++++++++++"+count+"+++++++++++++"); if(count==0){ msg = "null"; }else{ msg = "full"; } flag = true; }catch(Exception e){ System.out.println("真心對不起，你的程式出錯了"); e.printStackTrace(); }finally{ conn.close(); stmt.close(); } return flag ; } }
下面是實現資料庫連線類：
<pre name="code" class="java">package bookConnUtil;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class DBUtil {
public static final int CONNECTION_MYSQL=2;
public static final int CONNECTION_SQL=1;
public static final int CONNECTION_ODBC=0;
public DBUtil() { }
public static Connection getConnection(int connection_type)throws Exception
{
switch (connection_type)
{
case CONNECTION_ODBC:
return getConnectionODBC();
case CONNECTION_SQL:
return getConnectionSQL();
case CONNECTION_MYSQL:
return getConnectionMYSQL();
}
return null;
}
/**
* �ر����Ӷ���
*/
private static Connection getConnectionODBC()throws Exception
{
Connection conn=null;
try
{
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
System.out.println("abc");
conn=DriverManager.getConnection("jdbc:odbc:mybook","sa","123");
System.out.println("連線成功");
}
catch(Exception e)
{
e.printStackTrace();
throw e;
}
return conn;
}
private static Connection getConnectionSQL() throws Exception
{
Connection conn=null;
String connectionUrl = "jdbc:sqlserver://localhost:1433;databaseName=user;";
try
{
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
conn=DriverManager.getConnection(connectionUrl,"sa","123");
System.out.println("連線成功");
}
catch(Exception e)
{
e.printStackTrace();
throw e;
}
return conn;
}
private static Connection getConnectionMYSQL() throws Exception
{
String connectionUrl = "jdbc:mysql://localhost:3306/user";
String username = "root";
String password = "mysql";
Connection conn=null;
try
{
Class.forName("com.mysql.jdbc.Driver");
conn=DriverManager.getConnection(connectionUrl, username,password);
System.out.println("連線成功");
}
catch(Exception e)
{
e.printStackTrace();
throw e;
}
return conn;
}
public static void close(Connection conn) throws Exception
{
if(conn!=null)
{
try
{
conn.close();
}
catch(SQLException e)
{
e.printStackTrace();
throw e;
}
}
}
}
下面是實現使用者購物車搜尋類：
<pre name="code" class="java">package myCart;
import java.io.IOException;
import java.sql.SQLException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import bookConnUtil.bookDAO;
public class selectUserCart extends HttpServlet {
/**
*
*/
private static final long serialVersionUID = 1L;
public int count = myCartUtil.count;
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
// TODO Auto-generated method stub
HttpSession session=req.getSession();
String username =(String) session.getAttribute("username");
try {
//System.out.println("還沒執行到查詢過程這裡");
boolean flag=myCartUtil.selectUserCart(username);
if(flag==true){
/*for(mycart message:myCartUtil.list){
for(int i=0;i<3;i++){
String A = message.getUserName();
}
}*/
//session.setAttribute("count",countNum);
if(myCartUtil.msg.equals("null")){
session.setAttribute("null", myCartUtil.msg);
}else{
session.setAttribute("full", myCartUtil.msg);
}
req.getRequestDispatcher("selectMyAcccount.jsp").forward(req, resp);
}else{
req.getRequestDispatcher("error.html").forward(req, resp);
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
我的目錄實現程式碼：
<pre name="code" class="html"><%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Book Store</title>
<link rel="stylesheet" type="text/css" href="style.css" />
</head>
<body onload="selectUserCart">
<jsp:include page="head.jsp"/>
<div id="wrap">
<div class="center_content">
<div class="left_content">
<%
if(session.getAttribute("username") == null) {
%>
<script type="text/javascript" language="javascript">
alert("您還沒有登入，請登入...");
window.document.location.href="login.jsp";
</script>
<%
}
%>
<div class="title"><span class="title_icon"><img src="images/bullet1.gif" alt="" title="" /></span>My account</div>
<div class="feat_prod_box_details">
<p class="details"> 我還沒有什麼時間進行修改，所以使用的是以前的版本這樣的話造成的不便請您諒解。所有權為作者所有我還沒有什麼時間進行修改，所以使用的是以前的版本這樣的話造成的不便請您諒解。所有權為作者所有我還沒有什麼時間進行修改，所以使用的是以前的版本這樣的話造成的不便請您諒解。所有權為作者所有我還沒有什麼時間進行修改，所以使用的是以前的版本這樣的話造成的不便請您諒解。所有權為作者所有 </p>
<div class="contact_form">
<div class="form_subtitle">登陸 以檢視清單</div>
<form name="register" method="post" action="UserDAO">
<div class="form_row">
<label class="contact"><strong>使用者名稱:</strong></label>
<input type="text" class="contact_input" name="userName" />
</div>
<div class="form_row">
<label class="contact"><strong>密 碼:</strong></label>
<input type="password" class="con tact_input" name="password" />
</div>
<div class="form_row">
<div class="terms">
<input type="checkbox" name="terms" />
記住密碼 </div>
</div>
<div class="form_row">
<input type="submit" class="register" value="登陸" />
</div>
</form>
</div>
<div class="contact_form">
<div class="form_subtitle">更新書籍資訊</div>
<form name="updateBookMsg" method="post" action="updateBookMsg">
<div class="form_row">
<label class="contact"><strong>圖 書ID:</strong></label>
<input type="text" class="contact_input" name="bookId" />
</div>
<div class="form_row">
<label class="contact"><strong>圖 書 名:</strong></label>
<input type="text" class="contact_input" name="bookName" />
</div>
<div class="form_row">
<label class="contact"><strong>圖書簡介:</strong></label>
<input type="text" class="contact_input" name="pianduanName" />
</div>
<div class="form_row">
<input type="submit" class="register" value="提交" />
</div>
</form>
</div>
</div>
<div class="clear"></div>
</div>
<jsp:include page="broadside.jsp"/>
</div>
</div>
</body>
</html>