ASP写的文件下载代码

分类: 电脑/网络 >>程序设计 >>其他编程语言

问题描述:

在软件信息上有一个下载按钮：

<a href="down?filename=<%=rs("filename")%>"><img src=images/download.gif border=0></a>

在down上计算下载次数，并下载文件：

<!--#include file="conn"-->

<%

set rs2 = server.CreateObject ("Adodb.recordset")

sql2="update downtimes set downtimes=(downtimes+1) where filename="&request("filename")

rs2.open sql2,conn,1,1

set rs2=nothing

set rs = server.CreateObject ("Adodb.recordset")

sql="select * from upfile where filename="&request("filename")

rs.open sql,conn,1,1

Response.Redirect rs("filepath")

%>

filepath一般是“XXX.mp3”或“XXX.wma”、“XXX.doc”、“XXX”这样的名称，当点击下载按钮后，浏览器不显示下载对话框，而是直接在浏览器中播放或是显示这些文档或图片。请问有没有什么办法，不让浏览器调用本机播放器播放这些影音文件。当然，右键“目标另存为”可以下载，但是这样就不能计算文件的下载次数了，有两全其美的办法么？

解析:

Function downloadFile(strFile)

strFilename = server.MapPath(strFile)

Response.Buffer = True

Response.Clear

Set s = Server.CreateObject("ADODB.Stream")

s.Open

s.Type = 1

on error resume next

Set fso = Server.CreateObject("Scripting.FileSystemObject")

if not fso.FileExists(strFilename) then

Response.Write("<h1>Error:</h1>文件不存在<p>")

Response.End

end if

Set f = fso.GetFile(strFilename)

intFilelength = f.size

s.LoadFromFile(strFilename)

if err then

Response.Write("<h1>Error: </h1>" &err.Description &"<p>")

Response.End

end if

Response.AddHeader "Content-Disposition", "attachmentfilename=" &f.name

Response.AddHeader "Content-Length", intFilelength

Response.CharSet = "UTF-8"

Response.ContentType = "application/octet-stream"

Response.BinaryWrite s.Read

Response.Flush

s.Close

Set s = Nothing

End Function

看这个函数能帮到你吗

把下面的代码保存为download.asp，然后把下载链接改成<a href="Download.asp?FileName=***.rm">下载视频</a>就可以了：

<%FileName=Request.Querystring("FileName")

Function GetFileName(longname)

while instr(longname,"/")

longname=right(longname,len(longname)-1)

wend

GetFileName=longname

End Function

Const adTypeBinary=1

FileExt=Mid(FileName,InStrRev(FileName,".")+1)

Response.Clear

Response.AddHeader "content-disposition","attachmentfilename="&GetFileName(FileName)

Set Stream=server.CreateObject("ADODB.Stream")

Stream.Type=adTypeBinary

Stream.Open

'这里把DownloadFiles改成下载文件所在文件夹与本页的相对路径

TrueFileName="DownloadFiles/"&FileName

Stream.LoadFromFile Server.MapPath(TrueFileName)

While Not Stream.EOS

Response.BinaryWrite Stream.Read(1024*64)

Wend

Stream.Close

Set Stream=Nothing

Response.Flush

Response.End%>

using System

using System.Data

using System.Configuration

using System.Web

using System.Web.Security

using System.Web.UI

using System.Web.UI.WebControls

using System.Web.UI.WebControls.WebParts

using System.Web.UI.HtmlControls

using System.Text

using System.IO

public partial class _Default : System.Web.UI.Page

{

protected void Page_Load(object sender, EventArgs e)

{

DownloadClass dd = new DownloadClass()

dd.StrUrl = "http://127.0.0.1/UI.rar"

dd.StrFileName="C:\\1.rar"

dd.DownloadFile()

Response.Write(dd.strError)

}

//测试用线程1断点续传下载网络上的文件到本地电脑

public class DownloadClass

{

public string StrUrl//文件下载网址

public string StrFileName//下载文件保存地址

public string strError//返回结果

public long lStartPos = 0//返回上次下载字节

public long lCurrentPos = 0//返回当前下载字节

public long lDownloadFile//返回当前下载文件长度

public void DownloadFile()

{

System.IO.FileStream fs

if (System.IO.File.Exists(StrFileName))

{

fs = System.IO.File.OpenWrite(StrFileName)

lStartPos = fs.Length

fs.Seek(lStartPos, System.IO.SeekOrigin.Current)

//移动文件流中的当前指针

}

else

{

fs = new System.IO.FileStream(StrFileName, System.IO.FileMode.Create)

lStartPos = 0

}

//打开网络连接

try

{

System.Net.HttpWebRequest request = (System.Net.HttpWebRequest)System.Net.HttpWebRequest.Create(StrUrl)

long length = request.GetResponse().ContentLength

lDownloadFile = length

if (lStartPos >0)

request.AddRange((int)lStartPos)//设置Range值

//向服务器请求，获得服务器回应数据流

System.IO.Stream ns = request.GetResponse().GetResponseStream()

byte[] nbytes = new byte[512]

int nReadSize = 0

nReadSize = ns.Read(nbytes, 0, 512)

while (nReadSize >0)

{

fs.Write(nbytes, 0, nReadSize)

nReadSize = ns.Read(nbytes, 0, 512)

lCurrentPos = fs.Length

}

fs.Close()

ns.Close()

strError = "下载完成"

}

catch (Exception ex)

{

fs.Close()

strError = "下载过程中出现错误:" + ex.ToString()

}

}

}

}

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