<% @page import = "java.util.LinkedHashMap" %> |
<% @page import = "java.util.Map" %> |
<% @page import = "java.util.HashMap" %> |
<% @page import = "am_cn.itcast.domain.Student" %> |
<% @page import = "java.util.List" %> |
<% @page import = "java.util.ArrayList" %> |
<%@ 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 PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd" > |
<html> |
<head> |
<meta http-equiv= "Content-Type" content= "text/html; charset=UTF-8" > |
<title>Insert title here</title> |
</head> |
<body> |
<!-- 1 . 操作 javabean的 属性 , list 集合, map 集合, 数组 , 进行常规的 for 循环操作 |
主要 用于 做 循环的 ,遍历 ,取出 目标 中 的 每个 元素 . |
--> |
<% |
List list = new ArrayList(); |
list.add( new Student( "李寒" , 18 , "上海" )); |
list.add( new Student( "孙在驰" , 19 , "香港" )); |
list.add( new Student( "李羿成" , 17 , "东京" )); |
list.add( new Student( "高杰" , 19 , "湖北" )); |
list.add( new Student( "赵世龙" , 19 , "巴黎" )); |
list.add( new Student( "阿毛" , 19 , "上海" )); |
list.add( new Student( "宋勇" , 16 , "深圳" )); |
|
request.setAttribute( "list" , list); |
%> |
<c:forEach items= "${list }" var= "student" > |
${student.name } ${student.age } ${student.city } <br/> |
</c:forEach> |
|
<hr/> |
|
<c:forEach items= "${list }" var= "student" > |
${student.name } ${student.age } ${student.city } <br/> |
</c:forEach> |
<table border= "1" align= "center" width= "70%" > |
|
<tr> |
<td>索引</td> |
<td>是否是第一个</td> |
<td>是否是最后一个 </td> |
<td>姓名</td> |
<td>年龄</td> |
<td>城市</td> |
</tr> |
|
<c:forEach items= "${list }" var= "student" varStatus= "vs" > |
<tr bgcolor= "${vs.index%2==0?" #EBEBEB ":" #F8D890 " }" > |
<td>${vs.index }</td> |
<td>${vs. first}</td> |
<td>${vs.last }</td> |
<td>${student.name }</td> |
<td>${student.age } </td> |
<td>${student.city }</td> |
</tr> |
</c:forEach> |
</table> |
<hr/> |
|
<!-- 遍历 map 集合,取出 map 集合中的 数据 --> |
|
<% |
Map map = new LinkedHashMap(); |
|
map.put( "aaa" , "111" ); |
map.put( "bbb" , "222" ); |
map.put( "ccc" , "333" ); |
|
request.setAttribute( "map" , map); |
%> |
<c:forEach items= "${map }" var= "entry" > |
${entry.key } ${entry.value } <br/> |
</c:forEach> |
|
<!-- 遍历 数组 --> |
<% |
String[] names ={ "张柏芝" , "谢霆锋" , "王菲" , "文章" }; |
|
request.setAttribute( "names" , names); |
%> |
<c:forEach items= "${names }" var= "name" > |
${name } |
</c:forEach> |
|
<!-- 进行常规的 for 循环操作 --> |
|
<% |
// 求 1+2+3... + 9 的 和 |
|
int sum = 0 ; |
|
for ( int i= 1 ;i<= 9 ;i++){ |
sum+=i; |
} |
out.print(sum); |
%> |
|
<!-- 用 foreach 循环 怎么 做 ? --> |
|
<c:forEach begin= "1" end= "9" step= "1" var= "i" > |
<c:set var= "result" value= "${result+i }" ></c:set> |
</c:forEach> |
${result } |
</body> |
</html> |