S2jsp第三章 資料互動(二)
阿新 • • 發佈：2019-01-09
1.什麼是cookie？ cookie是由伺服器埠生成，傳送給客戶端的瀏覽器的，瀏覽器會將其儲存在某個目錄下的文字檔案中2.cookie作用？ 通過cookie，可以實現瀏覽器與伺服器之間的資料傳遞3.session和cookie的異同？ session與cookie均能實現資訊的儲存。 seesion是在伺服器儲存使用者資訊 session中儲存的是Object型別，cookie儲存的是String型別 seession物件會隨時關閉而結束，cookie可以長期儲存在客戶端 cookie通常用於不儲存不重要使用者資訊，重要的使用者資訊使用session儲存<%@ 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%>"> <title>註冊頁面</title> <meta http-equiv="pragma" content="no-cache"> <meta http-equiv="cache-control" content="no-cache"> <meta http-equiv="expires" content="0"> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="This is my page"> <!-- <link rel="stylesheet" type="text/css" href="styles.css"> --> </head> <body> <form action="do.jsp" method="post"> 使用者名稱：<input type="text" name="txtname" value="<%=request.getAttribute("name")%>"/> 密碼： <input type="password" name="txtpwd"/> <input type="submit" value="提交"/> </form> </body> </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%>">
<title>處理頁面</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
//session作用域
<body>
<%-- <%
<%
String name=request.getParameter("txtname");
String pwd=request.getParameter("txtpwd");
if("1".equals(name)&&"1".equals(pwd)){
session.setAttribute("name", name);
request.getRequestDispatcher("index.jsp").forward(request, response);
Cookie cook=new Cookie("name",name);
Cookie cookpwd=new Cookie("pwd",pwd);
response.addCookie(cook);
response.addCookie(cookpwd);
}else{
response.sendRedirect("register.jsp");
}
%>
</body>
</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%>"> <title>My JSP 'index.jsp' starting page</title> <meta http-equiv="pragma" content="no-cache"> <meta http-equiv="cache-control" content="no-cache"> <meta http-equiv="expires" content="0"> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="This is my page"> <!-- <link rel="stylesheet" type="text/css" href="styles.css"> --> </head> <body> <%-- 小指令碼： <%! boolean findyear(int year){ if((year%4==0&&year%100!=0)||year%400==0){ return true; }else{ return false; } } %> <% int count=0; for(int i=2000;i<2014;i++){ if(findyear(i)){ count++; } }%> 從2000-2013年期間,一共有<%=count %>個閏年 --%> <%-- 歡迎<%=request.getAttribute("name") %> --%> 歡迎 <%=session.getAttribute("name")%> <br/> <a href="/Day-0100/Login.jsp">登出</a> </body> </html>
<%@page import="java.nio.channels.SeekableByteChannel"%>
<%@ 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%>">
<title>My JSP 'Login.jsp' starting page</title>
</head>
<body>
<% //清除session
session.removeAttribute("name");
//跳轉到登入頁面
response.sendRedirect("/Day-0100/register.jsp");
%>
</body>
</html>
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>圖書列表</title>
</head>
<body>
<%@ include file="pandau.jsp" %>
</body>
</html>
<%@page import="java.nio.channels.SeekableByteChannel"%>
<%@ 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%>">
<title>My JSP 'pandau.jsp' starting page</title>
</head>
<body>
<% //判斷是否有session值
Object uname=session.getAttribute("name");
if(uname==null){
response.sendRedirect("register.jsp");
}
%>
</body>
</html>