java_web/webapp/expression.jsp
2024-12-16 19:45:31 +08:00

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<%@ page contentType="text/html;charset=GB2312" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<head>
<title>表达式相关的标签</title>
</head>
<body>
<h2>使用<c:out value="<c:out> <c:set> <c:remove>" />的例子</h2>
<hr>
<c:set scope="page" var="number">
<c:out value="${5}"/>
</c:set>
<br>
<c:set scope="request" var="number">
<c:out value="${15}"/>
</c:set>
<br>
<c:set scope="session" var="number">
<c:out value="${25}"/>
</c:set>
不同作用域的number变量的初始值</p>
pageScope.number =<c:out value="${pageScope.number}" default="No Data" />
<br>
requestScope.number =<c:out value="${requestScope.number}"
default="No Data" />
<br>
sessionScope.number =<c:out value="${sessionScope.number}"
default="No Data" />
<br>
<p><c:out value='执行<c:remove var="number" />之后'/></p>
<c:remove var="number" scope="request" />
pageScope.number =<c:out value="${pageScope.number}"
default="No Data" />
<br>
requestScope.number =<c:out value="${requestScope.number}"
default="No Data" />
<br>
sessionScope.number =<c:out value="${sessionScope.number}"
default="No Data" />
<br>
</body>
</html>