JSP-JSTL学习
<%@page import="com.Student"%> <%@page import="com.Person"%> <%@page import="sun.security.provider.MD2"%> <%@ page language="java" import="java.util.*" pageEncoding="utf-8"%> <%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> <jsp:useBean id="person" class="com.Person"></jsp:useBean> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> </head> <body> <h3>set赋值取值的四种方式</h3> <c:set value="张三" var="name1" scope="session"></c:set> <c:set var="name2" scope="session">李四</c:set> <c:set value="赵五" target="${person}" property="name"></c:set> <c:set target="${person}" property="age">19</c:set> <li>从session中得到的值:${sessionScope.name1}</li> <li>从session中得到的值:${sessionScope.name2}</li> <li>从Bean中获取对象person的name值:<c:out value="${person.name}"></c:out></li> <li>从Bean中获取对象person的age值:<c:out value="${person.age}"></c:out></li> <hr> <h3>set与bean进行赋值取值</h3> <c:set value="赵五" target="${person}" property="name"></c:set> <c:set target="${person}" property="age">19</c:set> <c:if test="${person.name == '赵武'}" var="name1"></c:if> <c:out value="name1的值:${name1}"></c:out><br/> <c:if test="${person.name == '赵五'}" var="name2"></c:if> <c:out value="name2的值:${name2}"></c:out> <hr> <h3>判断的使用</h3> <c:set var="score">65</c:set> <c:choose> <c:when test="${score>=90}"> 你的成绩为优秀! </c:when> <c:when test="${score>=70&&score<90}"> 您的成绩为良好! </c:when> <c:when test="${score>60&&score<70}"> 您的成绩为及格 </c:when> <c:otherwise> 对不起,您没有通过考试! </c:otherwise> </c:choose> <hr> <h3>foreach遍历集合</h3> <% List list = new ArrayList(); list.add("aaa"); list.add("bbb"); list.add("ccc"); list.add("ddd"); list.add("eee"); request.setAttribute("req", list); %> <c:forEach var="name" items="${req}"> <c:out value="${name}"></c:out><br/> </c:forEach> <hr> <c:forEach var="name" items="${req}" begin="1" end="4" step="1"> <c:out value="${name}"></c:out><br/> </c:forEach> <hr> <c:forEach var="name" items="${req}" begin="1" end="30" step="1" varStatus="s"> <c:out value="${name}"></c:out><br/> 所在位置:<c:out value="${s.index}"></c:out><br/> 总共已迭代的次数<c:out value="${s.count}"></c:out><br/> 是否为第一个位置:<c:out value="${s.first}"></c:out><br/> 是否为最后一个位置:<c:out value="${s.last}"></c:out><br/> </c:forEach> <hr> <c:forTokens var="t" items="1,2,3,4,5,6,7" delims=","> <c:out value="${t}"></c:out><br/> </c:forTokens> <hr> <h3>import文件路径的导入</h3> <c:catch var="error01"> <c:import url="http://www.baidu.com"></c:import> </c:catch> <c:out value="${error01 }"></c:out> <hr> <c:catch var="error02"> <c:import url="01.txt" charEncoding="gbk"></c:import> </c:catch> <hr> <c:catch var="error3"> <c:import var="myurl" url="01.txt" scope="session" charEncoding="gbk"></c:import> <c:out value="${myurl}"></c:out> <c:out value="${myurl}" /> </c:catch> <c:out value="${error3}"></c:out> <hr/> <h3>时间段的判断</h3> <jsp:useBean id="now" class="java.util.Date"></jsp:useBean> <c:choose> <c:when test="${now.hours>=0 && now.hours<5}">凌晨好</c:when> <c:when test="${now.hours>=5 && now.hours<8}">早上好</c:when> <c:when test="${now.hours>=8 && now.hours<11}">上午好</c:when> <c:when test="${now.hours>11 && now.hours<13}">中午好</c:when> <c:when test="${now.hours>=13 && now.hours<17}">下午好</c:when> <c:otherwise>晚上好</c:otherwise> </c:choose> 现在的时间是:${now.hours}时${now.minutes}分${now.seconds}秒 <hr/> <h3>登录记录</h3> <c:choose> <c:when test="${empty sessionScope.user}"> <form action="deal.jsp" method="post" name="form1"> <ul> <li>用户昵称:<input name="user" type="text" id="user" /></li> <li>密 码:<input name="pwd" type="password" id="pwd" /></li> <li><input name="Submit" type="submit" value="登录" /> <input name="Submit2" type="reset" value="重置" /></li> </ul> </form> </c:when> <c:otherwise> 欢迎${sessionScope.user}[<a href="logout.jsp">退出</a>] </c:otherwise> </c:choose> <hr/> <h3>异常的捕获与打印</h3> <c:catch var="exception"> <% int num = Integer.valueOf(request.getParameter("name")); out.print(num); %> </c:catch> <c:out value="${exception}"></c:out> <hr> <c:url var="path" value="register.jsp" scope="page"> <c:param name="user" value="mr"></c:param> <c:param name="email" value="wert"></c:param> </c:url> <a href="${pageScope.path}">提交</a> <hr> <%Random random = new Random(); %> <c:set var="luck"> <%=random.nextInt(10) %> </c:set> <c:choose> <c:when test="${luck==6}">恭喜你,中了一等奖!</c:when> <c:when test="${day==7}" >恭喜你,中了二等奖!</c:when> <c:when test="${day==8}">恭喜你,中了三等奖!</c:when> <c:otherwise>谢谢您的参与!</c:otherwise> </c:choose> <hr> <% int[] ages = { 1, 2, 3, 4, 5 }; List<String> list2 = new ArrayList<String>(); list2.add("12345"); list2.add("12365"); list2.add("12385"); list2.add("12325"); request.setAttribute("list", list2); Set<String> set = new TreeSet<String>(); // Set set.add("One"); set.add("One"); set.add("Two"); set.add("Three"); set.add("Set"); Map<String, String> map = new HashMap<String, String>(); // Map map.put("1", "黄彪"); map.put("2", "丫头"); map.put("3", "哥哥"); map.put("4", "笨蛋"); List<Student> list3 = new ArrayList<Student>(); list3.add(new Student("1111",11)); list3.add(new Student("43",14)); list3.add(new Student("143411",16)); list3.add(new Student("6765",12)); %> c:forEach遍历数组集合 <br/> <c:forEach var="age" items="<%= ages %>"> <c:out value="${age}" /> </c:forEach> <br/> c:forEach遍历List集合 <br/> <c:forEach items="${requestScope.list}" var="keyword" varStatus="id"> ${id.index}----${keyword}<br/> </c:forEach> c:forEach遍历Set集合 <br/> <c:forEach var="entry" items="<%= set %>"> <c:out value="${entry}" /> </c:forEach> <br/> c:forEach遍历Map集合 <br/> <c:forEach var="entry" items="<%= map %>"> <c:out value="${entry.key}"/>---<c:out value="${entry.value}"/> <br/> </c:forEach> <br/> c:forEach遍历List对象集合 <br/> <c:forEach var="info" items="<%=list3 %>"> <c:out value="${info.name }"></c:out>----<c:out value="${info.age }"></c:out><br/> </c:forEach> <br/> </body> </html>
package com; public class Student { private String name; private int age; public Student(String name,int age) { this.name = name; this.age = age; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } }