关于表单类型设为ENCTYPE="multipart/form-data"时的取值？

为了看着方便，简化一下
<%@ page import="java.sql.*" contentType="text/html;charset=GB2312"%>
<%@ page language="java" import="com.jspsmart.upload.*"%>
<jsp:useBean id="mySmartUpload" scope="page" class="com.jspsmart.upload.SmartUpload" />
<%
String Fname;
Fname = mySmartUpload.getRequest().getParameter("txtFname");
out.println(Fname);     //这里得到的就是null,怎么回事啊？
out.println(" 1111111111");
if (Fname != null){
out.println(" 222222222222");
}
else{
%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
</head>
<body bgcolor="#143C64" text="#000000" leftmargin="0" topmargin="10">
        <form name="form1" method="post" action="FileDownAdd.jsp" ENCTYPE="multipart/form-data">
              <input type="text" name="txtFname" value="asdfasd">
                <input type=submit name=submit1 value="submit">
        </form>
</body>
</html>
<%}%>