==Jsp==:java sever pages
翻譯 編譯 執行
jsp可以重用編譯好的Java源碼，提高速度。
- 註釋：
指令：
<%@ page language="java" import="java.util.*,java.text.*" contentType="text/html; charset=GBK" %>腳本：
<%
int numA = 4, numB = 5 ;
int result = numA+numB;
%>表達式 打印輸出：
<%=result %>方法體
<%！
String formatDate(Date d){
SimpleDateFormat formater = new SimpleDateFormat("yyyy年MM月dd日");
retrun formater.format(d);
}
%>
<%=formatDate(new Date()) %>
<%--方法可以在頁面多處調用--%>
==Jsp內置對象==
- out session request application response
- ==requsert==：用於處理客戶端請求。
| request對象方法 | 用處 |
|---|---|
| getParameter | 單個數據 |
| ParameterValues | 對應多個值時 |
| setCharacterEncoding | 請求的亂碼 |
| getRemoterAddr() | 返回客戶機地址 |
註冊login.jsp
<%@ 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 'test04.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>
<form name="form1" method="post" action="reginfo.jsp">
<table border="0" align="center">
<tr> <td>用戶名</td><td> <input type="text" name="name"></td></tr>
<tr><td>密碼</td><td > <input type="password" name="pwd"> </td></tr>
<tr> <td>您的信息來源</td><td>
<input type="checkbox" name="channel" value="報刊">報刊
<input type="checkbox" name="channel" value="網絡">網絡
<input type="checkbox" name="channel" value="朋友推薦"> 朋友推薦
<input type="checkbox" name="channel" value="電視"> 電視
</td></tr>
<!-- 以下是提交、取消按鈕 -->
<input type="submit" value="提交">
</table>
</form>
</body>
</html>
信息讀取reginfo.jsp
<%@ 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 'reginfo.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>
This is my JSP page.
<br>
<%
request.setCharacterEncoding("utf-8");
//讀取用戶名和密碼
String name = request.getParameter("name");
String pwd = request.getParameter("pwd");
%>
用戶名：<%=name%><br/>
密碼：<%=pwd%><br/>
信息來源：
<%
//讀取複選框選擇項
String[] channels = request.getParameterValues("channel");
if (channels != null) {
for (int i = 0; i < channels.length; i++) {
out.print("<br/>"+channels[i]);
}
}
%>
</body>
</html>
亂碼
<% ----以POST方式提交數據時----
//設置讀取請求信息的字符編碼爲GBK或者GB2312
request.setCharacterEncoding("GBK");
//讀取用戶名和密碼
String name = request.getParameter("name");
String pwd = request.getParameter("pwd");
%>