记录3种jsp下载文件的方法

[java]
<%
response.setContentType("application/x-download");//设置为下载application/x-download
String filedownload = "/要下载的文件名";//即将下载的文件的相对路径
String filedisplay = "最终要显示给用户的保存文件名";//下载文件时显示的文件保存名称
String filenamedisplay = URLEncoder.encode(filedisplay,"UTF-8");
response.addHeader("Content-Disposition","attachment;filename=" + filedisplay);

try
{
RequestDispatcher dis = application.getRequestDispatcher(filedownload);
if(dis!= null)
{
dis.forward(request,response);
}
response.flushBuffer();
}
catch(Exception e)
{
e.printStackTrace();
}
finally
{

}
%>

[javascript]
<%@page language="java" contentType="application/x-msdownload" pageEncoding="gb2312"%>
<%
//关于文件下载时采用文件流输出的方式处理：
//加上response.reset()，并且所有的％>后面不要换行，包括最后一个；

response.reset();//可以加也可以不加
response.setContentType("application/x-download");

//application.getRealPath("/main/mvplayer/CapSetup.msi");获取的物理路径

String filedownload = "想办法找到要提供下载的文件的物理路径＋文件名";
String filedisplay = "给用户提供的下载文件名";
String filedisplay = URLEncoder.encode(filedisplay,"UTF-8");
response.addHeader("Content-Disposition","attachment;filename=" + filedisplay);

java.io.OutputStream outp = null;
java.io.FileInputStream in = null;
try
{
outp = response.getOutputStream();
in = new FileInputStream(filenamedownload);

byte[] b = new byte[1024];
int i = 0;

while((i = in.read(b)) > 0)
{
outp.write(b, 0, i);
}
//
outp.flush();
//要加以下两句话，否则会报错
//java.lang.IllegalStateException: getOutputStream() has already been called for //this response
out.clear();
out = pageContext.pushBody();
}
catch(Exception e)
{
System.out.println("Error!");
e.printStackTrace();
}
finally
{
if(in != null)
{
in.close();
in = null;
}
//这里不能关闭
//if(outp != null)
//{
//outp.close();
//outp = null;
//}
}
%>

[java]
<%@ page language="java" import="java.util.*" pageEncoding="GBK"%>
<a href="do_download.jsp?url=xxxxxx">点击下载千千动听</a>

<%@ page language="java" import="java.util.*" pageEncoding="GBK"%>
<%@page import="com.jspsmart.upload.SmartUpload"%>

<%

    SmartUpload su=new SmartUpload();
    su.initialize(pageContext);
    su.setContentDisposition(null);//禁止浏览器打开文件只能下载
    su.downloadFile("upload/1.txt");
    //out.clear();
    //out=pageContext.pushBody();
%>

作者 cn_bboy

补充：Web开发 , Jsp ,