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如果我们知道一个静态文件的实际路径如:http://www.xx.com/download/51windows.pdf,如果服务器没有作特别的限制设置,我们就可以毫不费力的把它下载下来!当网站提供51windows.pdf下载时,怎么样才能让下载者无法得到他的实际路径呢!本文就来介绍如何使用Asp来隐藏文件的实际下载路径。 我们在管理网站文件时,可以把扩展名一样的文件放在同一个目录下,起一个比较特别名字,例如放pdf文件目录为the_pdf_file_s,把下面代码另存为down.asp,他的网上路径为http://www.xx.com/down.asp,我们就可以用http://www.xx.com/down.asp?FileName=citk.pdf来下载这个文件了,而且下载者无法看到这个文件实际下载路径的!在down.asp中我们还可以设置下载文件是否需要登陆,判断下载的来源页是否为外部网站,从而可以做到防止文件被盗链。 示例代码:(把#换成%) ------------------------------------------------------------------------------------------------------------------------ <# From_url = Cstr(Request.ServerVariables("HTTP_REFERER")) Serv_url = Cstr(Request.ServerVariables("SERVER_NAME")) if mid(From_url,8,len(Serv_url)) <> Serv_url then response.write "<b>非法链接!<br><span id=yu>3</span><a href=javascript:countDown></a>秒钟后系统将自动返回首页......</b>" response.write "<meta http-equiv=refresh content=3;url=index.asp>" response.write "<SCRIPT>valignbottom()</SCRIPT>" response.write "<script>function countDown(secs){yu.innerText=secs;if(--secs>0)setTimeout(’countDown(’+secs+’)’,1000);}countDown(3);</script>" response.end end if Function GetFileName(longname)’/folder1/folder2/file.asp=>file.asp while instr(longname,"/") longname = right(longname,len(longname)-1) wend GetFileName = longname End Function Dim Stream Dim Contents Dim FileName Dim TrueFileName Dim FileExt Const adTypeBinary = 1 FileName = Request.QueryString("FileName") if FileName = "" Then Response.Write "无效文件名!" Response.End End if FileExt = Mid(FileName, InStrRev(FileName, ".") + 1) Select Case UCase(FileExt) Case "ASP", "ASA", "ASPX", "ASAX", "MDB" Response.Write "非法操作!" Response.End End Select Response.Clear Response.AddHeader "content-disposition", "attachment; filename=" & GetFileName(Request.QueryString("FileName")) Set Stream = server.CreateObject("ADODB.Stream") Stream.Type = adTypeBinary Stream.Open if lcase(right(FileName,3))="rar" then ’设置文件类型 TrueFileName = "/files/"&FileName ’设置文件目录的相对路径 end if 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 #>

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