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<%@ page language="java" import="java.util.*" pageEncoding="ISO-8859-1"%> 
<%@ taglib uri="http://struts.apache.org/tags-bean" prefix="bean"%> 
<% 
String path = request.getContextPath(); 
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; String username="thanks"; 
request.setAttribute("username",username); %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> 
<html> 
  </head> 
  
  <body> 
    This is my JSP page. <br> 
    <bean:define id="username1" name="username" scope="request" toScope="session"> 
    </bean:define> 
    UserName: <bean:write name="username1"/> <BR> 
    UserName: ${sessionScope.username1} 
  </body> 
</html> 
我的页面怎么输出的没有${sessionScope.username1}的值呢，而是把这段代码输出来了。