jsp include兩種調用形式詳細

include有兩種形式,分別是Include指令：<%@ include file=""%>和include動作：<jsp教程:include page="" flush="true"/>

include調用檔案

<%@ include file=""%>，是將被引入的JSP與原JSP融合到一起，而這個融合過程是在翻譯階段進行的

index.jsp
 

<%@ page session="false" %>
<h3>Flavors</h3>
Our most popular flavors are:
<%@ include file="flavor_list.html" %>
Try them all!
 
flavor_list.html
 

<ol>
<li>Chocolate</li>
<li>Strawberry</li>
<li>Vanilla</li>
</ol>

 

常當應用程式中所有的頁面的某些部分（例如標題、頁尾和導覽列）都相同的時候，我們就可以考慮用include。具體在哪些時候用<%@ include file=""%>，哪些時候用<jsp:include page="" flush="true"/>。這種形式

include一個頁面的地址

<%@ page session="false" %>
<h3>Flavors</h3>
Our most popular flavors are:
<jsp:include page="/" flush="true"/>
Try them all!

根據使用者提交的參數請求，我們調用不用的檔案
執行個體

 

<%
   // Diameter of the earth in kilometers

   int distance = 12756;
%>
<%@ page session="false" %>
<h4>Diameter of the Earth in SI (Metric) Units</h4>
<jsp:include page="ShowDiameter.jsp" flush="true">
   <jsp:param name="dist" value="<%= distance %>" />
   <jsp:param name="units" value="SI" />
</jsp:include>

<h4>Diameter of the Earth in U.S. Customary Units</h4>
<jsp:include page="ShowDiameter.jsp" flush="true">
   <jsp:param name="dist" value="<%= distance %>" />
   <jsp:param name="units" value="US" />
</jsp:include>
 
ShowDiameter.jsp
 

<%@ page session="false"%>
<%
   String dist = request.getParameter("dist");
   if (dist == null)
      throw new ServletException
         ("No distance parameter specified");

   int kilometers = Integer.parseInt(dist);
   double miles = kilometers / 1.609344;

   String units = request.getParameter("units");
   if (units == null)
      throw new ServletException
         ("No units parameter specified");

   if (units.equals("SI")) {
   %> Diameter = <%= kilometers %> km <%
   }
   else {
   %> Diameter = <%= miles %> miles <%
   }
%>