asp图片防盗链--asp编程技术

<%
From_url = Cstr(Request.ServerVariables("HTTP_REFERER"))
Serv_url = Cstr(Request.ServerVariables("SERVER_NAME"))

'防止盗链，设置图片地址
if mid(From_url‚8‚len(Serv_url)) <> Serv_url then
response.redirect "此处输入你防盗链的地址（网址和图片都可以，演示本论坛有）"
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.End
End if
FileExt = Mid(FileName‚ InS

trRev(FileName‚ ".") + 1)

Response.Clear
if lcase(right(FileName‚3))="gif" or lcase(right(FileName‚3))="jpg" or lcase(right(FileName‚3))="png" then
Response.ContentType = "image/*" '对图像文件不出现下载对话框
else
Response.ContentType = "application/ms-download"
end if
Response.AddHeader "content-disposition"‚ "attachment; 200511212023261479711.htm=" & GetFileName(Request.QueryString("FileName"))
Set Stream = server.CreateObject("ADODB.Stream")
Stream.Type = adTypeBinary
Stream.Open
'设置服务器文件真实地址（如果你的论坛在ＢＢＳ目录下的话不许要作修改）
TrueFileName = "/bbs/images/upload（为了更加安全，请把上传的文件夹改名）/"&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
%>