如何能够自动将远程页面的文件中的图片下载到本地服务器？

* written by Jaron ,2003-11-12 */
/* 原出处：CSDN文档中心http://www.csdn.net/develop WEB技术中文网 http://www.jaron.cn */
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/* 自动创建目录，自动将原文件名更名，文件格式的限制以及其他功能的一些优化
/* 自动保存网页文件中 http://.... 格式的图片到本地

程序实现功能：自动将远程页面的文件中的图片下载到本地服务器

'将下文保存为 save2local.asp
'测试：save2local.asp?url=http://ent.sina.com.cn/s/m/2003-11-11/1411231388.html

<%
'参数设置开始
url = request("url")
localaddr = server.MapPath("images_remote/") '保存到本地的目录
localdir = "images_remote/" 'http 访问的相对路径
AllowFileExt = "jpg|bmp|png|gif" '支持的文件名格式
'参数设置完毕

if createdir(localaddr) = false then
response.Write "创建目录失败，请检查目录权限"
response.End
end if
response.Write Convert2LocalAddr(url,localaddr,localdir)

function Convert2LocalAddr(url,localaddr,localdir)
'参数说明
'url 页面地址
'localaddr 保存本地的物理地址
'localdir 相对路径
strContent = getHTTPPage(url)
Set objRegExp = New Regexp
objRegExp.IgnoreCase = True
objRegExp.Global = True
objRegExp.Pattern = "<img.+?>"
Set Matches =objRegExp.Execute(strContent)
For Each Match in Matches
RetStr = RetStr & GetRemoteImages(Match.Value)
Next
ImagesArray=split(RetStr,"||")
RemoteImage=""
LocalImage=""
for i=1 to ubound(ImagesArray)
if ImagesArray(i)<>"" and instr(RemoteImage,ImagesArray(i))<1 then
fname=baseurl&cstr(i&mid(ImagesArray(i),instrrev(ImagesArray(i),".")))
ImagesFileName = ImagesArray(i)
AllowFileExtArray = split(AllowFileExt,"|")
isGetFile = false
for tmp = 0 to ubound(AllowFileExtArray)
if lcase(GetFileExt(ImagesFileName)) = ALlowFileExtArray(tmp) then
isGetFile=True
end if
next
if isGetFile = true then
newfilename = GenerateRandomFileName(fname)
call Save2Local(ImagesFileName,localaddr & "/" & newfilename)
RemoteImage=RemoteImage&"||"& ImagesFileName
LocalImage=LocalImage&"||" & localdir & newfilename
end if
end if
next
arrnew=split(LocalImage,"||")
arrall=split(RemoteImage,"||")
for i=1 to ubound(arrnew)
strContent=replace(strContent,arrall(i),arrnew(i))
next
Convert2LocalAddr = strContent
end function

function GetRemoteImages(str)
Set objRegExp1 = New Regexp
objRegExp1.IgnoreCase = True
objRegExp1.Global = True
objRegExp1.Pattern = "http://.+? "
set mm=objRegExp1.Execute(str)
For Each Match1 in mm
tmpaddr = left(Match1.Value,len(Match1.Value)-1)
GetRemoteImages=GetRemoteImages&"||" & replace(replace(tmpaddr,"""",""),"'","")
next
end function

function getHTTPPage(url)
on error resume next
dim http
set http=Server.createobject("Msxml2.XMLHTTP")
Http.open "GET",url,false
Http.send()
if Http.readystate<>4 thenexit function
getHTTPPage=bytes2BSTR(Http.responseBody)
set http=nothing
if err.number<>0 then err.Clear
end function

Function bytes2BSTR(vIn)
dim strReturn
dim i,ThisCharCode,NextCharCode
strReturn = ""
For i = 1 To LenB(vIn)
ThisCharCode = AscB(MidB(vIn,i,1))
If ThisCharCode < &H80 Then
strReturn = strReturn & Chr(ThisCharCode)
Else
NextCharCode = AscB(MidB(vIn,i+1,1))
strReturn = strReturn & Chr(CLng(ThisCharCode) * &H100 + CInt(NextCharCode))
i = i + 1
End If
Next
bytes2BSTR = strReturn
End Function

function getHTTPimg(url)
on error resume next
dim http
set http=server.createobject("MSXML2.XMLHTTP")
Http.open "GET",url,false
Http.send()
if Http.readystate<>4 then exit function
getHTTPimg=Http.responseBody
set http=nothing
if err.number<>0 then err.Clear
end function

function Save2Local(from,tofile)
dim geturl,objStream,imgs
geturl=trim(from)
imgs=gethttpimg(geturl)
Set objStream = Server.CreateObject("ADODB.Stream")
objStream.Type =1
objStream.Open
objstream.write imgs
objstream.SaveToFile tofile,2
objstream.Close()
set objstream=nothing
end function

function geturlencodel(byval url)'中文文件名转换
Dim i,code
geturlencodel=""
if trim(Url)="" then exit function
for i=1 to len(Url)
code=Asc(mid(Url,i,1))
if code<0 Then code = code + 65536
If code>255 Then
geturlencodel=geturlencodel&"%"&Left(Hex(Code),2)&"%"&Right(Hex(Code),2)
else
geturlencodel=geturlencodel&mid(Url,i,1)
end if
next
end function

Function GenerateRandomFileName(ByVal szFilename) '根据原文件名，自动以日期YYYY-MM-DD-RANDOM格式生成新文件名
Randomize
ranNum = Int(90000 * Rnd) + 10000
If Month(Now) < 10 Then c_month = "0" & Month(Now) Else c_month = Month(Now)
If Day(Now) < 10 Then c_day = "0" & Day(Now) Else c_day = Day(Now)
If Hour(Now) < 10 Then c_hour = "0" & Hour(Now) Else c_hour = Hour(Now)
If Minute(Now) < 10 Then c_minute = "0" & Minute(Now) Else c_minute = Minute(Now)
If Second(Now) < 10 Then c_second = "0" & Second(Now) Else c_second = Minute(Now)
fileExt_a = Split(szFilename, ".")
FileExt = LCase(fileExt_a(UBound(fileExt_a)))
GenerateRandomFileName = Year(Now) & c_month & c_day & c_hour & c_minute & c_second & "_" & ranNum & "." & FileExt
End Function

Function CreateDIR(ByVal LocalPath) '建立目录的程序，如果有多级目录，则一级一级的创建
On Error Resume Next
LocalPath = Replace(LocalPath, "/", "/")
Set FileObject = server.CreateObject("Scripting.FileSystemObject")
patharr = Split(LocalPath, "/")
path_level = UBound(patharr)
For I = 0 To path_level
If I = 0 Then pathtmp = patharr(0) & "/" Else pathtmp = pathtmp & patharr(I) & "/"
cpath = Left(pathtmp, Len(pathtmp) - 1)
If Not FileObject.FolderExists(cpath) Then FileObject.CreateFolder cpath
Next
Set FileObject = Nothing
If Err.Number <> 0 Then
CreateDIR = False
Err.Clear
Else
CreateDIR = True
End If
End Function

function GetfileExt(byval filename)
fileExt_a=split(filename,".")
GetfileExt=lcase(fileExt_a(ubound(fileExt_a)))
end function
%>