jsp 学习

<%@ page import="java.util.ArrayList" %>
<%@ page import="java.util.HashMap" %>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
<h3>set的使用 SET标签</h3>
<c:set  var="name" value="蔡恒" scope="request"/>
${name}
<h3>c:if标签的使用</h3>
<c:set var="score" value="85" scope="request"/>
<c:if test="${score >=80 and score<=100}">
    你真厉害
</c:if>
<h3>foreach遍历</h3>
<%
    ArrayList<String> arr = new ArrayList<>();
    arr.add("操作");
    arr.add("曹操");
    arr.add("赵云");
    arr.add("李白");
    request.setAttribute("arr",arr);
%>
<c:forEach items="${arr}" var="name">
    ${name}
</c:forEach>

<h3>遍历域中的map集合</h3>
<%
    HashMap<String, String> map = new HashMap<>();
    map.put("name","赵云");
    map.put("age","56");
    map.put("addr","北京");
    map.put("desc","是中国的首都");
    request.setAttribute("Map",map);
%>
<c:forEach items="${Map}" var="entry">
    ${entry.getValue()}
    <br>
    ${entry.key}:${entry.value}
</c:forEach>

</body>
</html>
posted @ 2022-11-13 15:52  竹石2020  阅读(13)  评论(0编辑  收藏  举报