jstl--forEach

jstl和el表达式是开发当中常用的语言，而且通常都是夹着使用，来看看jstl中的循环语句forEach的基本用法
<%@page import="java.util.HashMap"%>
<%@page import="java.util.Map"%>
<%@page import="cn.hncu.domain.User"%>
<%@page import="java.util.ArrayList"%>
<%@page import="java.util.List"%>
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
	<%
		List<String> list = new ArrayList<String>();
		list.add("laoganma");
		list.add("shadingyu");
		list.add("duzitent");
		request.setAttribute("strList", list);
	%>

	<!-- 模拟for循环 -->
	<c:forEach begin="0" end="2" var="i">
		${i }<br>
		<!-- 
			 0
			 1
			 2
		 -->
	</c:forEach>
	
	<!-- 模拟foreach循环 -->
	<c:forEach items="${strList }" var = "str">
		${str}<br>
		<!-- 
			 laoganma
			 shadingyu
			 duzitent
		 -->
	</c:forEach>
	
	<%
		List<User> userList = new ArrayList<User>();
		User user1 = new User();
		user1.setId(1);
		user1.setName("shadingyu");
		user1.setPassword("111");
		User user2 = new User();
		user2.setId(2);
		user2.setName("shadingyu2");
		user2.setPassword("222");
		userList.add(user1);
		userList.add(user2);
		request.setAttribute("userList", userList);
		
		Map<String,User> map = new HashMap<String,User>();
		map.put("user1", user1);
		map.put("user2", user2);
		request.setAttribute("userMap", map);
	%>
	<c:forEach items="${userList }" var="user">
		${user.id } ${user.name} ${user.password}<br>
		<!-- 
			1 shadingyu 111
 			2 shadingyu2 222
		 -->
	</c:forEach>
	<c:forEach items="${userMap }" var="entry">
		${entry.key } --- ${entry.value} <br>
		<!-- 
			user1 --- User [id=1, name=shadingyu, password=111] 
 			user2 --- User [id=2, name=shadingyu2, password=222] 	
		 -->
	</c:forEach>
	<c:forEach items="${userMap }" var="entry">
		${entry.key } --- ${entry.value.name} <br>
		<!-- 
			user1 --- shadingyu 
 			user2 --- shadingyu2 
		 -->
	</c:forEach>
</body>
</html>
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