JSTL-core核心代码标签库中的forEach,remove, forTokens,choose,when,otherwise,redirect 标签

<%@ page language="java" import="java.util.*, cn.hncu.domain.*" pageEncoding="UTF-8"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
</head>

<body>

 c:forEach标签 
一、普通for循环的功能
<c:forEach begin="1" end="10" var="i" step="2">
${i} 
</c:forEach>

二、增强for循环的功能 
1.遍历数组 
<%
String strs[] = {"aa","bb","cc"};
pageContext.setAttribute("strs", strs);
%>
<c:forEach items="${strs}" var="str">
${str},
</c:forEach>

 
2.遍历List 
<%
List list = new ArrayList();
list.add("aaa");
list.add("bbb");
list.add("ccc");
pageContext.setAttribute("list", list);
%>
<c:forEach items="${list}" var="a">
${a},
</c:forEach>

 
3.遍历Map 
<%
Map map = new HashMap();
map.put("name", "李四");
map.put("age",24);
map.put("addr","安置小区");
pageContext.setAttribute("map", map);
%>
<c:forEach items="${map}" var="aa">
${aa} ==>   ${aa.key} , ${aa.value} 
</c:forEach>

 
3.遍历元素为值对象的集合,如List<User> 
<%
List<User> list2 = new ArrayList<User>();
list2.add( new User("Mike","1234",20));
list2.add( new User("Mike2","1234",22));
list2.add( new User("Mike3","4322",21));
list2.add( new User("Rose","111",10));
pageContext.setAttribute("list2", list2);
%>
<c:forEach items="${list2}" var="user" varStatus="idx">

${idx.index},${idx.count}: 
<c:out value="${user.name}"></c:out> ,
<c:out value="${user.pwd}"></c:out> ,
<c:out value="${user.age}"></c:out> 
</c:forEach>

<hr/>
 c:choose,when,otherwise标签 
<c:set var="score" value="65" scope="session"></c:set>
<c:choose>
<c:when test="${score>=90}">
优秀
</c:when>
<c:when test="${score>=80}">
良好
</c:when>
<c:when test="${score>=70}">
中等
</c:when>
<c:otherwise>
毕不了业
</c:otherwise>
</c:choose>

 forTokens标签 
<c:forTokens items="a,b,c,d,23,tt" delims="," var="x">
${x} 
</c:forTokens>

 url相关的标签: url,import,redirect 

<a href="<c:url value='/ShowServlet' />">显示所有用户信息</a> 

<c:import url="/jsps/foot.jsp"></c:import>

<%--小心，页面中写了c:redirect，就会立即重定向到其它页面。不会再停留在当前页面
<c:redirect url="/jsps/show.jsp"></c:redirect>
response.sendRedirect("/jsps/show.jsp");
--%>

 c:remove标签：移除属性变量, 和set是相反 
<c:remove var="score"/>
score: ${score}

</body>
</html>

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JSTL-core核心代码标签库中的forEach,remove, forTokens,choose,when,otherwise,redirect 标签

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