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<td width="90%"><font size="4" face="Verdana, Arial, Helvetica"><b>示例问题</b></font></td><td width="200" align="right"><font size="1" face="Verdana, Arial, Helvetica"><nobr> 第 5 页（共5 页）</nobr></font></td>
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<font size="2" face="Verdana, Arial, Helvetica"><b>问题 1：</b>
<p>考虑下面的代码段：</p>
<pre>
<code style="font-family: Courier New, Courier, monospace; font-size: 12">
<%! String filePath = "Helloworld.jsp"%>
<%@ include file="<%= filePath %>"%>
</code>
</pre>
<p>这将在当前 JSP 文件中包含 Helloworld.jsp 的内容。选择正确的选项：</p>
<p>
<b>选择：</b>
</p>
<ul>
<li>
<b>A.</b> 正确</li>
<li>
<b>B.</b> 错误</li>
</ul>
<p>
<b>正确答案：</b>
</p>
<ul>
<li>
<b>B</b>
</li>
</ul>
<p>
<b>说明：</b>
</p>
<p>当使用 <code>include</code> 指令包含文件时，包含处理是在转换时完成的。但 reqeust-time 属性值是在请求时，而不是在转换时计算的。因此，file 的属性值不能是表达式，它必须是一个字符串文本值。也记住，file 的属性值不能把任何参数传递给被包含的页面，因此下面的例子是无效的：</p>
<pre>
<code style="font-family: Courier New, Courier, monospace; font-size: 12">
<%@ include file="Helloworld.jsp?planet=Earth" %>
</code>
</pre>
<p>
<b>问题 2：</b>
</p>
<p>下面哪项可用于在文件 test.jsp 中包含文件 another.jsp（假设没有错误发生）？</p>
<p>
<b>文件 1：test.jsp</b>
</p>
<pre>
<code style="font-family: Courier New, Courier, monospace; font-size: 12">
<% String str="hello"; % >
// line 1
<%= str%>
%>
</code>
</pre>
<p>
<b>文件 2：another.jsp</b>
</p>
<pre>
<code style="font-family: Courier New, Courier, monospace; font-size: 12">
<% str+="world"; %>
</code>
</pre>
<p>
<b>选择：</b>
</p>
<ul>
<li>
<b>A.</b> <code><jsp:directive.include file="another.jsp"/></code>
</li>
<li>
<b>B.</b> <code><%@ include page="another.jsp" %></code>
</li>
<li>
<b>C.</b> <code><%@ include file="another.jsp" %></code>
</li>
<li>
<b>D.</b> <code><jsp:include page="another.jsp"/></code>
</li>
<li>
<b>E.</b> <code><jsp:include file="another.jsp"/></code>
</li>
</ul>
<p>
<b>正确答案：</b>
</p>
<ul>
<li>
<b>C</b>
</li>
</ul>
<p>
<b>说明：</b>
</p>
<p>这里，another.jsp 没有声明变量 <code>str</code>，因此它不能独立进行编译。注意，当动态包含 JSP 文件时，它是另外进行编译的，因此，变量不在包含文件和被包含文件之间共享。在本例中，动态包含是不可能的，因此选项 C 和 D 是不正确的（D 也有一个无效的属性）。选项 A 是不正确的。因为在同一个页面中，不能同时使用 XML 语法和 JSP 语法。选项 B 是不正确的。因为 <code>include</code> 指令的有效属性是 <code>file</code>，而不是
<code>page</code>。</p>
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