jsp入门程序
<%@ page contentType="text/html/xml" %>
<%--@ taglib prefix="c" uri="http://www.csdn.net" --%>
<html>
<head>
<title>JSP is Easy</title>
</head>
<body bgcolor ="white">
<h1>JSP is as easy as ...</h1>
<%-- Calculate the sum of 1 + 2 + 3 dynamically --%>
1 + 2 + 3 = <c:out value="${1 + 2 + 3}" />
</body>
</html>
输出的结果应该是1 + 2 + 3 = 6
可为什么只输出了1 + 2 + 3 =
请问这是为什么?