如何将文件从浏览器上传到运行经典 ASP 的服务器并在服务器端检测文件是否为有效图片？对于有效图片，如何获取其尺寸？
通常经典 ASP 中的文件上传是由第三方组件完成的，这些组件带有一个 DLL 文件并且需要在服务器上注册，有时还需要花钱。毋庸置疑，出于安全原因，许多主机不允许使用第三方组件。
已经有很多纯 ASP 上传脚本，但它们只取文件并保存到服务器磁盘，没有任何图像检测。
以下是我自己为上述目的编写的脚本，但当然欢迎使用替代方案或更好的方法提供更多答案。
【问题讨论】：
这是一个处理文件上传和图像检测的类。用例将在下面。按原样保存，最好保存为新文件，扩展名为.asp，例如ShadowUpload.asp
注意：如果您想允许上传大于 200kb 的图片，请查看Request.BinaryRead(Request.TotalBytes) throws error for large files 的回复。 （否则可能会导致 BinaryRead 行出现“不允许操作”错误。）
<%
'constants:
Const MAX_UPLOAD_SIZE=1500000 'bytes
Const MSG_NO_DATA="nothing to upload!"
Const MSG_EXCEEDED_MAX_SIZE="you exceeded the maximum upload size!"
Const SU_DEBUG_MODE=False
Class ShadowUpload
Private m_Request
Private m_Files
Private m_Error
Public Property Get GetError
GetError = m_Error
End Property
Public Property Get FileCount
FileCount = m_Files.Count
End Property
Public Function File(index)
Dim keys
keys = m_Files.Keys
Set File = m_Files(keys(index))
End Function
Public Default Property Get Item(strName)
If m_Request.Exists(strName) Then
Item = m_Request(strName)
Else
Item = ""
End If
End Property
Private Sub Class_Initialize
Dim iBytesCount, strBinData
'first of all, get amount of uploaded bytes:
iBytesCount = Request.TotalBytes
WriteDebug("initializing upload, bytes: " & iBytesCount & "<br />")
'abort if nothing there:
If iBytesCount=0 Then
m_Error = MSG_NO_DATA
Exit Sub
End If
'abort if exceeded maximum upload size:
If iBytesCount>MAX_UPLOAD_SIZE Then
m_Error = MSG_EXCEEDED_MAX_SIZE
Exit Sub
End If
'read the binary data:
strBinData = Request.BinaryRead(iBytesCount)
'create private collections:
Set m_Request = Server.CreateObject("Scripting.Dictionary")
Set m_Files = Server.CreateObject("Scripting.Dictionary")
'populate the collection:
Call BuildUpload(strBinData)
End Sub
Private Sub Class_Terminate
Dim fileName
If IsObject(m_Request) Then
m_Request.RemoveAll
Set m_Request = Nothing
End If
If IsObject(m_Files) Then
For Each fileName In m_Files.Keys
Set m_Files(fileName)=Nothing
Next
m_Files.RemoveAll
Set m_Files = Nothing
End If
End Sub
Private Sub BuildUpload(ByVal strBinData)
Dim strBinQuote, strBinCRLF, iValuePos
Dim iPosBegin, iPosEnd, strBoundaryData
Dim strBoundaryEnd, iCurPosition, iBoundaryEndPos
Dim strElementName, strFileName, objFileData
Dim strFileType, strFileData, strElementValue
strBinQuote = AsciiToBinary(chr(34))
strBinCRLF = AsciiToBinary(chr(13))
'find the boundaries
iPosBegin = 1
iPosEnd = InstrB(iPosBegin, strBinData, strBinCRLF)
strBoundaryData = MidB(strBinData, iPosBegin, iPosEnd-iPosBegin)
iCurPosition = InstrB(1, strBinData, strBoundaryData)
strBoundaryEnd = strBoundaryData & AsciiToBinary("--")
iBoundaryEndPos = InstrB(strBinData, strBoundaryEnd)
'read binary data into private collection:
Do until (iCurPosition>=iBoundaryEndPos) Or (iCurPosition=0)
'skip non relevant data...
iPosBegin = InstrB(iCurPosition, strBinData, AsciiToBinary("Content-Disposition"))
iPosBegin = InstrB(iPosBegin, strBinData, AsciiToBinary("name="))
iValuePos = iPosBegin
'read the name of the form element, e.g. "file1", "text1"
iPosBegin = iPosBegin+6
iPosEnd = InstrB(iPosBegin, strBinData, strBinQuote)
strElementName = BinaryToAscii(MidB(strBinData, iPosBegin, iPosEnd-iPosBegin))
'maybe file?
iPosBegin = InstrB(iCurPosition, strBinData, AsciiToBinary("filename="))
iPosEnd = InstrB(iPosEnd, strBinData, strBoundaryData)
If (iPosBegin>0) And (iPosBegin<iPosEnd) Then
'skip non relevant data..
iPosBegin = iPosBegin+10
'read file name:
iPosEnd = InstrB(iPosBegin, strBinData, strBinQuote)
strFileName = BinaryToAscii(MidB(strBinData, iPosBegin, iPosEnd-iPosBegin))
'verify that we got name:
If Len(strFileName)>0 Then
'create file data:
Set objFileData = New FileData
objFileData.FileName = strFileName
'read file type:
iPosBegin = InstrB(iPosEnd, strBinData, AsciiToBinary("Content-Type:"))
iPosBegin = iPosBegin+14
iPosEnd = InstrB(iPosBegin, strBinData, strBinCRLF)
strFileType = BinaryToAscii(MidB(strBinData, iPosBegin, iPosEnd-iPosBegin))
objFileData.ContentType = strFileType
'read file contents:
iPosBegin = iPosEnd+4
iPosEnd = InstrB(iPosBegin, strBinData, strBoundaryData)-2
strFileData = MidB(strBinData, iPosBegin, iPosEnd-iPosBegin)
'check that not empty:
If LenB(strFileData)>0 Then
objFileData.Contents = strFileData
'append to files collection if not empty:
Set m_Files(strFileName) = objFileData
Else
Set objFileData = Nothing
End If
End If
strElementValue = strFileName
Else
'ordinary form value, just read:
iPosBegin = InstrB(iValuePos, strBinData, strBinCRLF)
iPosBegin = iPosBegin+4
iPosEnd = InstrB(iPosBegin, strBinData, strBoundaryData)-2
strElementValue = BinaryToAscii(MidB(strBinData, iPosBegin, iPosEnd-iPosBegin))
End If
'append to request collection
m_Request(strElementName) = strElementValue
'skip to next element:
iCurPosition = InstrB(iCurPosition+LenB(strBoundaryData), strBinData, strBoundaryData)
Loop
End Sub
Private Function WriteDebug(msg)
If SU_DEBUG_MODE Then
Response.Write(msg)
Response.Flush
End If
End Function
Private Function AsciiToBinary(strAscii)
Dim i, char, result
result = ""
For i=1 to Len(strAscii)
char = Mid(strAscii, i, 1)
result = result & chrB(AscB(char))
Next
AsciiToBinary = result
End Function
Private Function BinaryToAscii(strBinary)
Dim i, result
result = ""
For i=1 to LenB(strBinary)
result = result & chr(AscB(MidB(strBinary, i, 1)))
Next
BinaryToAscii = result
End Function
End Class
Class FileData
Private m_fileName
Private m_contentType
Private m_BinaryContents
Private m_AsciiContents
Private m_imageWidth
Private m_imageHeight
Private m_checkImage
Public Property Get FileName
FileName = m_fileName
End Property
Public Property Get ContentType
ContentType = m_contentType
End Property
Public Property Get ImageWidth
If m_checkImage=False Then Call CheckImageDimensions
ImageWidth = m_imageWidth
End Property
Public Property Get ImageHeight
If m_checkImage=False Then Call CheckImageDimensions
ImageHeight = m_imageHeight
End Property
Public Property Let FileName(strName)
Dim arrTemp
arrTemp = Split(strName, "\")
m_fileName = arrTemp(UBound(arrTemp))
End Property
Public Property Let CheckImage(blnCheck)
m_checkImage = blnCheck
End Property
Public Property Let ContentType(strType)
m_contentType = strType
End Property
Public Property Let Contents(strData)
m_BinaryContents = strData
m_AsciiContents = RSBinaryToString(m_BinaryContents)
End Property
Public Property Get Size
Size = LenB(m_BinaryContents)
End Property
Private Sub CheckImageDimensions
Dim width, height, colors
Dim strType
'''If gfxSpex(BinaryToAscii(m_BinaryContents), width, height, colors, strType) = true then
If gfxSpex(m_AsciiContents, width, height, colors, strType) = true then
m_imageWidth = width
m_imageHeight = height
End If
m_checkImage = True
End Sub
Private Sub Class_Initialize
m_imageWidth = -1
m_imageHeight = -1
m_checkImage = False
End Sub
Public Sub SaveToDisk(strFolderPath, ByRef strNewFileName)
Dim strPath, objFSO, objFile
Dim i, time1, time2
Dim objStream, strExtension
strPath = strFolderPath&"\"
If Len(strNewFileName)=0 Then
strPath = strPath & m_fileName
Else
strExtension = GetExtension(strNewFileName)
If Len(strExtension)=0 Then
strNewFileName = strNewFileName & "." & GetExtension(m_fileName)
End If
strPath = strPath & strNewFileName
End If
WriteDebug("save file started...<br />")
time1 = CDbl(Timer)
Set objFSO = Server.CreateObject("Scripting.FileSystemObject")
Set objFile = objFSO.CreateTextFile(strPath)
objFile.Write(m_AsciiContents)
'''For i=1 to LenB(m_BinaryContents)
''' objFile.Write chr(AscB(MidB(m_BinaryContents, i, 1)))
'''Next
time2 = CDbl(Timer)
WriteDebug("saving file took " & (time2-time1) & " seconds.<br />")
objFile.Close
Set objFile=Nothing
Set objFSO=Nothing
End Sub
Private Function GetExtension(strPath)
Dim arrTemp
arrTemp = Split(strPath, ".")
GetExtension = ""
If UBound(arrTemp)>0 Then
GetExtension = arrTemp(UBound(arrTemp))
End If
End Function
Private Function RSBinaryToString(xBinary)
'Antonin Foller, http://www.motobit.com
'RSBinaryToString converts binary data (VT_UI1 | VT_ARRAY Or MultiByte string)
'to a string (BSTR) using ADO recordset
Dim Binary
'MultiByte data must be converted To VT_UI1 | VT_ARRAY first.
If vartype(xBinary)=8 Then Binary = MultiByteToBinary(xBinary) Else Binary = xBinary
Dim RS, LBinary
Const adLongVarChar = 201
Set RS = CreateObject("ADODB.Recordset")
LBinary = LenB(Binary)
If LBinary>0 Then
RS.Fields.Append "mBinary", adLongVarChar, LBinary
RS.Open
RS.AddNew
RS("mBinary").AppendChunk Binary
RS.Update
RSBinaryToString = RS("mBinary")
Else
RSBinaryToString = ""
End If
End Function
Function MultiByteToBinary(MultiByte)
'© 2000 Antonin Foller, http://www.motobit.com
' MultiByteToBinary converts multibyte string To real binary data (VT_UI1 | VT_ARRAY)
' Using recordset
Dim RS, LMultiByte, Binary
Const adLongVarBinary = 205
Set RS = CreateObject("ADODB.Recordset")
LMultiByte = LenB(MultiByte)
If LMultiByte>0 Then
RS.Fields.Append "mBinary", adLongVarBinary, LMultiByte
RS.Open
RS.AddNew
RS("mBinary").AppendChunk MultiByte & ChrB(0)
RS.Update
Binary = RS("mBinary").GetChunk(LMultiByte)
End If
MultiByteToBinary = Binary
End Function
Private Function WriteDebug(msg)
If SU_DEBUG_MODE Then
Response.Write(msg)
Response.Flush
End If
End Function
Private Function BinaryToAscii(strBinary)
Dim i, result
result = ""
For i=1 to LenB(strBinary)
result = result & chr(AscB(MidB(strBinary, i, 1)))
Next
BinaryToAscii = result
End Function
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
'::: :::
'::: This routine will attempt to identify any filespec passed :::
'::: as a graphic file (regardless of the extension). This will :::
'::: work with BMP, GIF, JPG and PNG files. :::
'::: :::
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
'::: Based on ideas presented by David Crowell :::
'::: (credit where due) :::
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
'::: blah blah blah blah blah blah blah blah blah blah blah blah :::
'::: blah blah blah blah blah blah blah blah blah blah blah blah :::
'::: blah blah Copyright *c* MM, Mike Shaffer blah blah :::
'::: bh blah ALL RIGHTS RESERVED WORLDWIDE blah blah :::
'::: blah blah Permission is granted to use this code blah blah :::
'::: blah blah in your projects, as long as this blah blah :::
'::: blah blah copyright notice is included blah blah :::
'::: blah blah blah blah blah blah blah blah blah blah blah blah :::
'::: blah blah blah blah blah blah blah blah blah blah blah blah :::
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
'::: :::
'::: This function gets a specified number of bytes from any :::
'::: file, starting at the offset (base 1) :::
'::: :::
'::: Passed: :::
'::: flnm => Filespec of file to read :::
'::: offset => Offset at which to start reading :::
'::: bytes => How many bytes to read :::
'::: :::
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
Private Function GetBytes(flnm, offset, bytes)
Dim startPos
If offset=0 Then
startPos = 1
Else
startPos = offset
End If
if bytes = -1 then ' Get All!
GetBytes = flnm
else
GetBytes = Mid(flnm, startPos, bytes)
end if
' Dim objFSO
' Dim objFTemp
' Dim objTextStream
' Dim lngSize
'
' Set objFSO = CreateObject("Scripting.FileSystemObject")
'
' ' First, we get the filesize
' Set objFTemp = objFSO.GetFile(flnm)
' lngSize = objFTemp.Size
' set objFTemp = nothing
'
' fsoForReading = 1
' Set objTextStream = objFSO.OpenTextFile(flnm, fsoForReading)
'
' if offset > 0 then
' strBuff = objTextStream.Read(offset - 1)
' end if
'
' if bytes = -1 then ' Get All!
' GetBytes = objTextStream.Read(lngSize) 'ReadAll
' else
' GetBytes = objTextStream.Read(bytes)
' end if
'
' objTextStream.Close
' set objTextStream = nothing
' set objFSO = nothing
End Function
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
'::: :::
'::: Functions to convert two bytes to a numeric value (long) :::
'::: (both little-endian and big-endian) :::
'::: :::
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
Private Function lngConvert(strTemp)
lngConvert = clng(asc(left(strTemp, 1)) + ((asc(right(strTemp, 1)) * 256)))
end function
Private Function lngConvert2(strTemp)
lngConvert2 = clng(asc(right(strTemp, 1)) + ((asc(left(strTemp, 1)) * 256)))
end function
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
'::: :::
'::: This function does most of the real work. It will attempt :::
'::: to read any file, regardless of the extension, and will :::
'::: identify if it is a graphical image. :::
'::: :::
'::: Passed: :::
'::: flnm => Filespec of file to read :::
'::: width => width of image :::
'::: height => height of image :::
'::: depth => color depth (in number of colors) :::
'::: strImageType=> type of image (e.g. GIF, BMP, etc.) :::
'::: :::
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
function gfxSpex(flnm, width, height, depth, strImageType)
dim strPNG
dim strGIF
dim strBMP
dim strType
dim strBuff
dim lngSize
dim flgFound
dim strTarget
dim lngPos
dim ExitLoop
dim lngMarkerSize
strType = ""
strImageType = "(unknown)"
gfxSpex = False
strPNG = chr(137) & chr(80) & chr(78)
strGIF = "GIF"
strBMP = chr(66) & chr(77)
strType = GetBytes(flnm, 0, 3)
if strType = strGIF then ' is GIF
strImageType = "GIF"
Width = lngConvert(GetBytes(flnm, 7, 2))
Height = lngConvert(GetBytes(flnm, 9, 2))
Depth = 2 ^ ((asc(GetBytes(flnm, 11, 1)) and 7) + 1)
gfxSpex = True
elseif left(strType, 2) = strBMP then ' is BMP
strImageType = "BMP"
Width = lngConvert(GetBytes(flnm, 19, 2))
Height = lngConvert(GetBytes(flnm, 23, 2))
Depth = 2 ^ (asc(GetBytes(flnm, 29, 1)))
gfxSpex = True
elseif strType = strPNG then ' Is PNG
strImageType = "PNG"
Width = lngConvert2(GetBytes(flnm, 19, 2))
Height = lngConvert2(GetBytes(flnm, 23, 2))
Depth = getBytes(flnm, 25, 2)
select case asc(right(Depth,1))
case 0
Depth = 2 ^ (asc(left(Depth, 1)))
gfxSpex = True
case 2
Depth = 2 ^ (asc(left(Depth, 1)) * 3)
gfxSpex = True
case 3
Depth = 2 ^ (asc(left(Depth, 1))) '8
gfxSpex = True
case 4
Depth = 2 ^ (asc(left(Depth, 1)) * 2)
gfxSpex = True
case 6
Depth = 2 ^ (asc(left(Depth, 1)) * 4)
gfxSpex = True
case else
Depth = -1
end select
else
strBuff = GetBytes(flnm, 0, -1) ' Get all bytes from file
lngSize = len(strBuff)
flgFound = 0
strTarget = chr(255) & chr(216) & chr(255)
flgFound = instr(strBuff, strTarget)
if flgFound = 0 then
exit function
end if
strImageType = "JPG"
lngPos = flgFound + 2
ExitLoop = false
do while ExitLoop = False and lngPos < lngSize
do while asc(mid(strBuff, lngPos, 1)) = 255 and lngPos < lngSize
lngPos = lngPos + 1
loop
if asc(mid(strBuff, lngPos, 1)) < 192 or asc(mid(strBuff, lngPos, 1)) > 195 then
lngMarkerSize = lngConvert2(mid(strBuff, lngPos + 1, 2))
lngPos = lngPos + lngMarkerSize + 1
else
ExitLoop = True
end if
loop
if ExitLoop = False then
Width = -1
Height = -1
Depth = -1
else
Height = lngConvert2(mid(strBuff, lngPos + 4, 2))
Width = lngConvert2(mid(strBuff, lngPos + 6, 2))
Depth = 2 ^ (asc(mid(strBuff, lngPos + 8, 1)) * 8)
gfxSpex = True
end if
end if
End Function
End Class
%>
常量解释：
MAX_UPLOAD_SIZE - 所有上传文件的最大大小，以字节为单位。当超过该大小时，上传过程中止，全局错误设置为常量 MSG_EXCEEDED_MAX_SIZE。
MSG_NO_DATA - 当用户没有选择要上传的任何文件时，全局错误将设置为该常量。
SU_DEBUG_MODE - 当设置为True 时，脚本将通过Response.Write() 输出各种消息，对调试问题很有用。
简单用例：（完整代码）
<!-- #include file="ShadowUpload.asp" -->
<%
Dim objUpload
If Request("action")="1" Then
Set objUpload=New ShadowUpload
If objUpload.GetError<>"" Then
Response.Write("sorry, could not upload: "&objUpload.GetError)
Else
Response.Write("found "&objUpload.FileCount&" files...<br />")
For x=0 To objUpload.FileCount-1
Response.Write("file name: "&objUpload.File(x).FileName&"<br />")
Response.Write("file type: "&objUpload.File(x).ContentType&"<br />")
Response.Write("file size: "&objUpload.File(x).Size&"<br />")
Response.Write("image width: "&objUpload.File(x).ImageWidth&"<br />")
Response.Write("image height: "&objUpload.File(x).ImageHeight&"<br />")
If (objUpload.File(x).ImageWidth>200) Or (objUpload.File(x).ImageHeight>200) Then
Response.Write("image to big, not saving!")
Else
Call objUpload.File(x).SaveToDisk(Server.MapPath("Uploads"), "")
Response.Write("file saved successfully!")
End If
Response.Write("<hr />")
Next
Response.Write("thank you, "&objUpload("name"))
End If
End If
%>
<form action="<%=Request.ServerVariables( "Script_Name" )%>?action=1" enctype="multipart/form-data" method="POST">
File1: <input type="file" name="file1" /><br />
File2: <input type="file" name="file2" /><br />
File3: <input type="file" name="file3" /><br />
Name: <input type="text" name="name" /><br />
<button type="submit">Upload</button>
</form>
这演示了使用大多数脚本功能，阻止非图像文件上传，您可以使用以下内容：
If objUpload.File(x).ImageWidth<0 Then
Response.Write("Not a valid image!")
Else
'proceed to save the file...
End If
免责声明：这最初是在七年前发布的 here，并且正如代码本身所记，包含不是我编写的部分。
在安卓设备上使用 Chrome 浏览器的客户注意事项：
由于某种原因，submit 类型的标准 <button> 元素似乎无法在 Chrome for android 中正常工作。如果您收到客户的投诉，请尝试在表单中更改此行：
<button type="submit">Upload</button>
改为：
<input type="submit" value="Upload" />
由于 Android 版 Chrome 应用程序中可能存在错误，当使用手机的相机应用程序拍摄新图像然后尝试提交此图像时，可能会失败。在这种情况下，只需建议客户端使用不同的浏览器即可。
【讨论】：
Response.Write("thank you, "&objUpload("name"))。这将显示用户在输入元素中写的内容，例如<input type="text" name="name" />。
@ShadowWizard 的代码很好，可以在本地机器上运行，但我在生产服务器上遇到了上传问题，然后我用更强大的上传请求解析例程重写了 Class。
该类现在可以处理更多错误，您可以使用单个 INPUT 元素上传多个文件；将此另存为新文件并将其重命名为“uploadhelper.asp”
<%
Const MAX_UPLOAD_SIZE = 25000000 '25 MB
Const MSG_NO_DATA = "Nothing to upload."
Const MSG_EXCEEDED_MAX_SIZE = "You exceeded the maximum upload size."
Const MSG_BAD_REQUEST_METHOD = "Bad request method. Use the POST method."
Const MSG_BAD_ENCTYPE = "Bad encoding type. Use a ""multipart/form-data"" enctype."
Const MSG_ZERO_LENGTH = "Zero length request."
Class UploadHelper
Private m_Request
Private m_Files
Private m_Error
Public Property Get GetError
GetError = m_Error
End Property
Public Property Get FileCount
FileCount = m_Files.Count
End Property
Public Function File(index)
If m_Files.Exists(index) Then
Set File = m_Files(index)
Else
Set File = Nothing
End If
End Function
Public Default Property Get Item(strName)
If m_Request.Exists(strName) Then
Item = m_Request(strName)
Else
Item = ""
End If
End Property
Private Sub Class_Initialize
Dim iBytesCount, strBinData
'first of all, get amount of uploaded bytes:
iBytesCount = Request.TotalBytes
'abort if nothing there:
If iBytesCount = 0 Then
m_Error = MSG_NO_DATA
Exit Sub
End If
'abort if exceeded maximum upload size:
If iBytesCount > MAX_UPLOAD_SIZE Then
m_Error = MSG_EXCEEDED_MAX_SIZE
Exit Sub
End If
If Request.ServerVariables("REQUEST_METHOD") = "POST" Then
Dim CT, PosB, Boundary, PosE
CT = Request.ServerVariables("HTTP_Content_Type")
If LCase(Left(CT, 19)) = "multipart/form-data" Then
PosB = InStr(LCase(CT), "boundary=")
If PosB > 0 Then Boundary = Mid(CT, PosB + 9)
PosB = InStr(LCase(CT), "boundary=")
If PosB > 0 Then
PosB = InStr(Boundary, ",")
If PosB > 0 Then Boundary = Left(Boundary, PosB - 1)
End If
If iBytesCount > 0 And Boundary <> "" Then
Boundary = "--" & Boundary
Dim Head, Binary
Binary = Request.BinaryRead(iBytesCount)
'create private collections:
Set m_Request = Server.CreateObject("Scripting.Dictionary")
Set m_Files = Server.CreateObject("Scripting.Dictionary")
Call ParseRequest(Binary, Boundary)
Binary = Empty
Else
m_Error = MSG_ZERO_LENGTH
Exit Sub
End If
Else
m_Error = MSG_BAD_ENCTYPE
Exit Sub
End If
Else
m_Error = MSG_BAD_REQUEST_METHOD
Exit Sub
End If
End Sub
Private Sub Class_Terminate
Dim fileName
If IsObject(m_Request) Then
m_Request.RemoveAll
Set m_Request = Nothing
End If
If IsObject(m_Files) Then
For Each fileName In m_Files.Keys
Set m_Files(fileName)=Nothing
Next
m_Files.RemoveAll
Set m_Files = Nothing
End If
End Sub
Private Sub ParseRequest(Binary, Boundary)
Dim PosOpenBoundary, PosCloseBoundary, PosEndOfHeader, isLastBoundary
Boundary = StringToBinary(Boundary)
PosOpenBoundary = InStrB(Binary, Boundary)
PosCloseBoundary = InStrB(PosOpenBoundary + LenB(Boundary), Binary, Boundary, 0)
Dim HeaderContent, FieldContent, bFieldContent
Dim Content_Disposition, FormFieldName, SourceFileName, Content_Type
Dim TwoCharsAfterEndBoundary, n : n = 0
Do While (PosOpenBoundary > 0 And PosCloseBoundary > 0 And Not isLastBoundary)
PosEndOfHeader = InStrB(PosOpenBoundary + Len(Boundary), Binary, StringToBinary(vbCrLf + vbCrLf))
HeaderContent = MidB(Binary, PosOpenBoundary + LenB(Boundary) + 2, PosEndOfHeader - PosOpenBoundary - LenB(Boundary) - 2)
bFieldContent = MidB(Binary, (PosEndOfHeader + 4), PosCloseBoundary - (PosEndOfHeader + 4) - 2)
GetHeadFields BinaryToString(HeaderContent), Content_Disposition, FormFieldName, SourceFileName, Content_Type
Set objFileData = New FileData
objFileData.FileName = SourceFileName
objFileData.ContentType = Content_Type
objFileData.Contents = bFieldContent
objFileData.FormFieldName = FormFieldName
objFileData.ContentDisposition = Content_Disposition
Set m_Files(n) = objFileData
Set objFileData = Nothing
TwoCharsAfterEndBoundary = BinaryToString(MidB(Binary, PosCloseBoundary + LenB(Boundary), 2))
isLastBoundary = TwoCharsAfterEndBoundary = "--"
If Not isLastBoundary Then
PosOpenBoundary = PosCloseBoundary
PosCloseBoundary = InStrB(PosOpenBoundary + LenB(Boundary), Binary, Boundary)
End If
n = n + 1
Loop
End Sub
Private Function GetHeadFields(ByVal Head, Content_Disposition, Name, FileName, Content_Type)
Content_Disposition = LTrim(SeparateField(Head, "content-disposition:", ";"))
Name = (SeparateField(Head, "name=", ";"))
If Left(Name, 1) = """" Then Name = Mid(Name, 2, Len(Name) - 2)
FileName = (SeparateField(Head, "filename=", ";"))
If Left(FileName, 1) = """" Then FileName = Mid(FileName, 2, Len(FileName) - 2)
Content_Type = LTrim(SeparateField(Head, "content-type:", ";"))
End Function
Private Function SeparateField(From, ByVal sStart, ByVal sEnd)
Dim PosB, PosE, sFrom
sFrom = LCase(From)
PosB = InStr(sFrom, sStart)
If PosB > 0 Then
PosB = PosB + Len(sStart)
PosE = InStr(PosB, sFrom, sEnd)
If PosE = 0 Then PosE = InStr(PosB, sFrom, vbCrLf)
If PosE = 0 Then PosE = Len(sFrom) + 1
SeparateField = Mid(From, PosB, PosE - PosB)
Else
SeparateField = Empty
End If
End Function
Private Function BinaryToString(Binary)
dim cl1, cl2, cl3, pl1, pl2, pl3
Dim L
cl1 = 1
cl2 = 1
cl3 = 1
L = LenB(Binary)
Do While cl1<=L
pl3 = pl3 & Chr(AscB(MidB(Binary,cl1,1)))
cl1 = cl1 + 1
cl3 = cl3 + 1
if cl3>300 then
pl2 = pl2 & pl3
pl3 = ""
cl3 = 1
cl2 = cl2 + 1
if cl2>200 then
pl1 = pl1 & pl2
pl2 = ""
cl2 = 1
End If
End If
Loop
BinaryToString = pl1 & pl2 & pl3
End Function
Private Function StringToBinary(String)
Dim I, B
For I=1 to len(String)
B = B & ChrB(Asc(Mid(String,I,1)))
Next
StringToBinary = B
End Function
End Class
Class FileData
Private m_fileName
Private m_contentType
Private m_BinaryContents
Private m_AsciiContents
Private m_imageWidth
Private m_imageHeight
Private m_checkImage
Private m_formFieldName
Private m_contentDisposition
Public Property Get FormFieldName
FormFieldName = m_formFieldName
End Property
Public Property Let FormFieldName(sFieldName)
m_formFieldName = sFieldName
End Property
Public Property Get ContentDisposition
ContentDisposition = m_contentDisposition
End Property
Public Property Let ContentDisposition(sContentDisposition)
m_contentDisposition = sContentDisposition
End Property
Public Property Get FileName
FileName = m_fileName
End Property
Public Property Get ContentType
ContentType = m_contentType
End Property
Public Property Get ImageWidth
If m_checkImage=False Then Call CheckImageDimensions
ImageWidth = m_imageWidth
End Property
Public Property Get ImageHeight
If m_checkImage=False Then Call CheckImageDimensions
ImageHeight = m_imageHeight
End Property
Public Property Let FileName(ByVal strName)
strName = Replace(strName, "/", "\")
Dim arrTemp : arrTemp = Split(strName, "\")
m_fileName = arrTemp(UBound(arrTemp))
End Property
Public Property Let CheckImage(blnCheck)
m_checkImage = blnCheck
End Property
Public Property Let ContentType(strType)
m_contentType = strType
End Property
Public Property Let Contents(strData)
m_BinaryContents = strData
m_AsciiContents = RSBinaryToString(m_BinaryContents)
End Property
Public Property Get Size
Size = LenB(m_BinaryContents)
End Property
Private Sub CheckImageDimensions
Dim width, height, colors
Dim strType
'''If gfxSpex(BinaryToAscii(m_BinaryContents), width, height, colors, strType) = true then
If gfxSpex(m_AsciiContents, width, height, colors, strType) = true then
m_imageWidth = width
m_imageHeight = height
End If
m_checkImage = True
End Sub
Private Sub Class_Initialize
m_imageWidth = -1
m_imageHeight = -1
m_checkImage = False
End Sub
Public Sub SaveToDisk(strFolderPath, ByRef strNewFileName)
Dim strPath, objFSO, objFile
Dim i, time1, time2
Dim objStream, strExtension
strPath = strFolderPath&"\"
If Len(strNewFileName)=0 Then
strPath = strPath & m_fileName
Else
strExtension = GetExtension(strNewFileName)
If Len(strExtension)=0 Then
strNewFileName = strNewFileName & "." & GetExtension(m_fileName)
End If
strPath = strPath & strNewFileName
End If
time1 = CDbl(Timer)
Set objFSO = Server.CreateObject("Scripting.FileSystemObject")
Set objFile = objFSO.CreateTextFile(strPath)
objFile.Write(m_AsciiContents)
'''For i=1 to LenB(m_BinaryContents)
''' objFile.Write chr(AscB(MidB(m_BinaryContents, i, 1)))
'''Next
time2 = CDbl(Timer)
objFile.Close
Set objFile=Nothing
Set objFSO=Nothing
End Sub
Private Function GetExtension(strPath)
Dim arrTemp
arrTemp = Split(strPath, ".")
GetExtension = ""
If UBound(arrTemp)>0 Then
GetExtension = arrTemp(UBound(arrTemp))
End If
End Function
Private Function RSBinaryToString(xBinary)
'Antonin Foller, http://www.motobit.com
'RSBinaryToString converts binary data (VT_UI1 | VT_ARRAY Or MultiByte string)
'to a string (BSTR) using ADO recordset
Dim Binary
'MultiByte data must be converted To VT_UI1 | VT_ARRAY first.
If vartype(xBinary)=8 Then Binary = MultiByteToBinary(xBinary) Else Binary = xBinary
Dim RS, LBinary
Const adLongVarChar = 201
Set RS = CreateObject("ADODB.Recordset")
LBinary = LenB(Binary)
If LBinary>0 Then
RS.Fields.Append "mBinary", adLongVarChar, LBinary
RS.Open
RS.AddNew
RS("mBinary").AppendChunk Binary
RS.Update
RSBinaryToString = RS("mBinary")
Else
RSBinaryToString = ""
End If
End Function
Function MultiByteToBinary(MultiByte)
'© 2000 Antonin Foller, http://www.motobit.com
' MultiByteToBinary converts multibyte string To real binary data (VT_UI1 | VT_ARRAY)
' Using recordset
Dim RS, LMultiByte, Binary
Const adLongVarBinary = 205
Set RS = CreateObject("ADODB.Recordset")
LMultiByte = LenB(MultiByte)
If LMultiByte>0 Then
RS.Fields.Append "mBinary", adLongVarBinary, LMultiByte
RS.Open
RS.AddNew
RS("mBinary").AppendChunk MultiByte & ChrB(0)
RS.Update
Binary = RS("mBinary").GetChunk(LMultiByte)
End If
MultiByteToBinary = Binary
End Function
Private Function BinaryToAscii(strBinary)
Dim i, result
result = ""
For i=1 to LenB(strBinary)
result = result & chr(AscB(MidB(strBinary, i, 1)))
Next
BinaryToAscii = result
End Function
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
'::: :::
'::: This routine will attempt to identify any filespec passed :::
'::: as a graphic file (regardless of the extension). This will :::
'::: work with BMP, GIF, JPG and PNG files. :::
'::: :::
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
'::: Based on ideas presented by David Crowell :::
'::: (credit where due) :::
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
'::: blah blah blah blah blah blah blah blah blah blah blah blah :::
'::: blah blah blah blah blah blah blah blah blah blah blah blah :::
'::: blah blah Copyright *c* MM, Mike Shaffer blah blah :::
'::: bh blah ALL RIGHTS RESERVED WORLDWIDE blah blah :::
'::: blah blah Permission is granted to use this code blah blah :::
'::: blah blah in your projects, as long as this blah blah :::
'::: blah blah copyright notice is included blah blah :::
'::: blah blah blah blah blah blah blah blah blah blah blah blah :::
'::: blah blah blah blah blah blah blah blah blah blah blah blah :::
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
'::: :::
'::: This function gets a specified number of bytes from any :::
'::: file, starting at the offset (base 1) :::
'::: :::
'::: Passed: :::
'::: flnm => Filespec of file to read :::
'::: offset => Offset at which to start reading :::
'::: bytes => How many bytes to read :::
'::: :::
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
Private Function GetBytes(flnm, offset, bytes)
Dim startPos
If offset=0 Then
startPos = 1
Else
startPos = offset
End If
if bytes = -1 then ' Get All!
GetBytes = flnm
else
GetBytes = Mid(flnm, startPos, bytes)
end if
' Dim objFSO
' Dim objFTemp
' Dim objTextStream
' Dim lngSize
'
' Set objFSO = CreateObject("Scripting.FileSystemObject")
'
' ' First, we get the filesize
' Set objFTemp = objFSO.GetFile(flnm)
' lngSize = objFTemp.Size
' set objFTemp = nothing
'
' fsoForReading = 1
' Set objTextStream = objFSO.OpenTextFile(flnm, fsoForReading)
'
' if offset > 0 then
' strBuff = objTextStream.Read(offset - 1)
' end if
'
' if bytes = -1 then ' Get All!
' GetBytes = objTextStream.Read(lngSize) 'ReadAll
' else
' GetBytes = objTextStream.Read(bytes)
' end if
'
' objTextStream.Close
' set objTextStream = nothing
' set objFSO = nothing
End Function
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
'::: :::
'::: Functions to convert two bytes to a numeric value (long) :::
'::: (both little-endian and big-endian) :::
'::: :::
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
Private Function lngConvert(strTemp)
lngConvert = clng(asc(left(strTemp, 1)) + ((asc(right(strTemp, 1)) * 256)))
end function
Private Function lngConvert2(strTemp)
lngConvert2 = clng(asc(right(strTemp, 1)) + ((asc(left(strTemp, 1)) * 256)))
end function
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
'::: :::
'::: This function does most of the real work. It will attempt :::
'::: to read any file, regardless of the extension, and will :::
'::: identify if it is a graphical image. :::
'::: :::
'::: Passed: :::
'::: flnm => Filespec of file to read :::
'::: width => width of image :::
'::: height => height of image :::
'::: depth => color depth (in number of colors) :::
'::: strImageType=> type of image (e.g. GIF, BMP, etc.) :::
'::: :::
':::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
function gfxSpex(flnm, width, height, depth, strImageType)
dim strPNG
dim strGIF
dim strBMP
dim strType
dim strBuff
dim lngSize
dim flgFound
dim strTarget
dim lngPos
dim ExitLoop
dim lngMarkerSize
strType = ""
strImageType = "(unknown)"
gfxSpex = False
strPNG = chr(137) & chr(80) & chr(78)
strGIF = "GIF"
strBMP = chr(66) & chr(77)
strType = GetBytes(flnm, 0, 3)
if strType = strGIF then ' is GIF
strImageType = "GIF"
Width = lngConvert(GetBytes(flnm, 7, 2))
Height = lngConvert(GetBytes(flnm, 9, 2))
Depth = 2 ^ ((asc(GetBytes(flnm, 11, 1)) and 7) + 1)
gfxSpex = True
elseif left(strType, 2) = strBMP then ' is BMP
strImageType = "BMP"
Width = lngConvert(GetBytes(flnm, 19, 2))
Height = lngConvert(GetBytes(flnm, 23, 2))
Depth = 2 ^ (asc(GetBytes(flnm, 29, 1)))
gfxSpex = True
elseif strType = strPNG then ' Is PNG
strImageType = "PNG"
Width = lngConvert2(GetBytes(flnm, 19, 2))
Height = lngConvert2(GetBytes(flnm, 23, 2))
Depth = getBytes(flnm, 25, 2)
select case asc(right(Depth,1))
case 0
Depth = 2 ^ (asc(left(Depth, 1)))
gfxSpex = True
case 2
Depth = 2 ^ (asc(left(Depth, 1)) * 3)
gfxSpex = True
case 3
Depth = 2 ^ (asc(left(Depth, 1))) '8
gfxSpex = True
case 4
Depth = 2 ^ (asc(left(Depth, 1)) * 2)
gfxSpex = True
case 6
Depth = 2 ^ (asc(left(Depth, 1)) * 4)
gfxSpex = True
case else
Depth = -1
end select
else
strBuff = GetBytes(flnm, 0, -1) ' Get all bytes from file
lngSize = len(strBuff)
flgFound = 0
strTarget = chr(255) & chr(216) & chr(255)
flgFound = instr(strBuff, strTarget)
if flgFound = 0 then
exit function
end if
strImageType = "JPG"
lngPos = flgFound + 2
ExitLoop = false
do while ExitLoop = False and lngPos < lngSize
do while asc(mid(strBuff, lngPos, 1)) = 255 and lngPos < lngSize
lngPos = lngPos + 1
loop
if asc(mid(strBuff, lngPos, 1)) < 192 or asc(mid(strBuff, lngPos, 1)) > 195 then
lngMarkerSize = lngConvert2(mid(strBuff, lngPos + 1, 2))
lngPos = lngPos + lngMarkerSize + 1
else
ExitLoop = True
end if
loop
if ExitLoop = False then
Width = -1
Height = -1
Depth = -1
else
Height = lngConvert2(mid(strBuff, lngPos + 4, 2))
Width = lngConvert2(mid(strBuff, lngPos + 6, 2))
Depth = 2 ^ (asc(mid(strBuff, lngPos + 8, 1)) * 8)
gfxSpex = True
end if
end if
End Function
End Class
%>
用法：使用以下代码创建一个新的 *.asp 文件来上传您的文件。
<!-- #include file="uploadhelper.asp" -->
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title></title>
</head>
<body>
<form action="<%=Request.ServerVariables("SCRIPT_NAME")%>?cmd=upload" method="POST" enctype="multipart/form-data">
File: <input type="file" name="files[]" multiple>
<input type="submit" value="Upload">
</form>
<%
If Request("cmd")="upload" Then
Dim objUpload : Set objUpload = New UploadHelper
If objUpload.GetError <> "" Then
Response.Write("Warning: "&objUpload.GetError)
Else
Response.Write("found "&objUpload.FileCount&" files...<br />")
Dim x : For x = 0 To objUpload.FileCount - 1
Response.Write("form field name: "&objUpload.File(x).FormFieldName&"<br />")
Response.Write("content disposition: "&objUpload.File(x).ContentDisposition&"<br />")
Response.Write("file name: "&objUpload.File(x).FileName&"<br />")
Response.Write("file type: "&objUpload.File(x).ContentType&"<br />")
Response.Write("file size: "&objUpload.File(x).Size&"<br />")
Response.Write("image width: "&objUpload.File(x).ImageWidth&"<br />")
Response.Write("image height: "&objUpload.File(x).ImageHeight&"<br />")
If (objUpload.File(x).ImageWidth>1024) Or (objUpload.File(x).ImageHeight>1024) Then
Response.Write("the image is too big, file not saved!")
Else
Call objUpload.File(x).SaveToDisk(Server.MapPath("/public"), "")
Response.Write("file saved successfully!")
End If
Response.Write("<hr />")
Next
End If
End If
%>
</body>
</html>
【讨论】：
作为 PPS，问题可能比您想象的要简单一些。 IIS 对 BinaryRead() 函数调用的限制为 200K。有人在尝试实施此解决方案时遇到此问题吗？
为什么在最初的文档中没有提到 BinaryRead() 限制？我已经为此苦苦挣扎了一个多小时。
StackOverflow 上的这个链接解释了它：Request.BinaryRead(Request.TotalBytes) throws error for large files
【讨论】：