jspsmartupload 下载实现

 

down.html代码如下：原理就是通过超链接到一个jsp，通过jsp调用下载的代码

<! DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" >
< html >
     < head >
         < title > 文件上传 </ title >
         < meta  http-equiv ="Content-Type"  content ="text/html; charset=gb2312" >
     </ head >
     < body >
         < p  align ="center" >
            上传文件选择
         </ p >
         < FORM  METHOD ="POST"  ACTION ="up.jsp"  ENCTYPE ="multipart/form-data" >
             < input  type ="hidden"  name ="TEST"  value ="good" >
             < table  width ="75%"  border ="1"  align ="center" >
                 < tr >
                     < td >
                         < div  align ="center" >
                            1、
                             < input  type ="FILE"  name ="FILE1"  size ="30" >
                         </ div >
                     </ td >
                 </ tr >
                 < tr >
                     < td >
                         < div  align ="center" >
                            2、
                             < input  type ="FILE"  name ="FILE2"  size ="30" >
                         </ div >
                     </ td >
                 </ tr >
                 < tr >
                     < td >
                         < div  align ="center" >
                            3、
                             < input  type ="FILE"  name ="FILE3"  size ="30" >
                         </ div >
                     </ td >
                 </ tr >
                 < tr >
                     < td >
                         < div  align ="center" >
                            4、
                             < input  type ="FILE"  name ="FILE4"  size ="30" >
                         </ div >
                     </ td >
                 </ tr >
                 < tr >
                     < td >
                         < div  align ="center" >
                             < input  type ="submit"  name ="Submit"  value ="上传它！" >
                         </ div >
                     </ td >
                 </ tr >
             </ table >
             < br >
             < br >
             < a  href ="down.jsp"   > 点击下载 </ a >
         </ FORM >
     </ body >
</ html >

down.jsp

 

<% ... @page contentType="text/html; charset=gb2312" language="java" import="java.util.*,com.jspsmart.upload.*,java.lang.*" errorPage=""  %>

<! DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" >
< html >
   < head >

     < title > My JSP 'down.jsp' starting page </ title >

   </ head >
  
   < body >
         <% ... SmartUpload su=new SmartUpload();
                su.initialize(pageContext);
                su.setContentDisposition(null);//是否自动打开，null为不自动打开
                su.downloadFile("c:/jh.cer");
                out.clear(); 
                out = pageContext.pushBody();                         
             %>         
   </ body >
</ html >

值得主义的是：再<%%>里的后两句

out.clear();
out = pageContext.pushBody();
一定要加上，不然在有些时候会报异常：getOutputStream() has already been called for this response