查了很久，原来是form这没有加上这个　enctype="multipart/form-data"



Set upload=new upload_5xsoft
Set file1=upload.file("photo") ''生成一个文件对象
If file1.FileSize>80720 Then
Set file1=nothing
Set upload=nothing
Response.Write "<Script Language=""javascript"">"&vbcrlf&"<!--"&vbcrlf
Response.Write "alert(""附图文件已大于30K，不允许新增！"");"&vbcrlf
Response.Write "history.back();"&vbcrlf&"</Script>"
Response.end
End If

这段为什么会出错呢？
错误：
无效的过程调用或参数: 'MidB'

付上：upload_5xsoft.inc

－－－－－－－－－－－－－－
<SCRIPT RUNAT=SERVER LANGUAGE=VBSCRIPT>
dim Data_5xsoft

Class upload_5xsoft

dim objForm,objFile,Version

Public function Form(strForm)
strForm=lcase(strForm)
if not objForm.exists(strForm) then
Form=""
else
Form=objForm(strForm)
end if
end function

Public function File(strFile)
strFile=lcase(strFile)
if not objFile.exists(strFile) then
set File=new FileInfo
else
set File=objFile(strFile)
end if
end function


Private Sub Class_Initialize
dim RequestData,sStart,vbCrlf,sInfo,iInfoStart,iInfoEnd,tStream,iStart,theFile
dim iFileSize,sFilePath,sFileType,sFormvalue,sFileName
dim iFindStart,iFindEnd
dim iFormStart,iFormEnd,sFormName
Version="化境HTTP上传程序 Version 2.0"
set objForm=Server.CreateObject("Scripting.Dictionary")
set objFile=Server.CreateObject("Scripting.Dictionary")
if Request.TotalBytes<1 then Exit Sub
set tStream = Server.CreateObject("adodb.stream")
set Data_5xsoft = Server.CreateObject("adodb.stream")
Data_5xsoft.Type = 1
Data_5xsoft.Mode =3
Data_5xsoft.Open
Data_5xsoft.Write Request.BinaryRead(Request.TotalBytes)
Data_5xsoft.Position=0
RequestData =Data_5xsoft.Read

iFormStart = 1
iFormEnd = LenB(RequestData)
vbCrlf = chrB(13) & chrB(10)
sStart = MidB(RequestData,1, InStrB(iFormStart,RequestData,vbCrlf)-1)
iStart = LenB (sStart)
iFormStart=iFormStart+iStart+1
while (iFormStart + 10) < iFormEnd
    iInfoEnd = InStrB(iFormStart,RequestData,vbCrlf & vbCrlf)+3
    tStream.Type = 1
    tStream.Mode =3
    tStream.Open
    Data_5xsoft.Position = iFormStart
    Data_5xsoft.CopyTo tStream,iInfoEnd-iFormStart
    tStream.Position = 0
    tStream.Type = 2
    tStream.Charset ="gb2312"
    sInfo = tStream.ReadText
    tStream.Close
    '取得表单项目名称
    iFormStart = InStrB(iInfoEnd,RequestData,sStart)
    iFindStart = InStr(22,sInfo,"name=""",1)+6
    iFindEnd = InStr(iFindStart,sInfo,"""",1)
    sFormName = lcase(Mid (sinfo,iFindStart,iFindEnd-iFindStart))
    '如果是文件
    if InStr (45,sInfo,"filename=""",1) > 0 then
        set theFile=new FileInfo
        '取得文件名
        iFindStart = InStr(iFindEnd,sInfo,"filename=""",1)+10
        iFindEnd = InStr(iFindStart,sInfo,"""",1)
        sFileName = Mid (sinfo,iFindStart,iFindEnd-iFindStart)
        theFile.FileName=getFileName(sFileName)
        theFile.FilePath=getFilePath(sFileName)
        '取得文件类型
        iFindStart = InStr(iFindEnd,sInfo,"Content-Type: ",1)+14
        iFindEnd = InStr(iFindStart,sInfo,vbCr)
        theFile.FileType =Mid (sinfo,iFindStart,iFindEnd-iFindStart)
        theFile.FileStart =iInfoEnd
        theFile.FileSize = iFormStart -iInfoEnd -3
        theFile.FormName=sFormName
        if not objFile.Exists(sFormName) then
         objFile.add sFormName,theFile
        end if
    else
    '如果是表单项目
        tStream.Type =1
        tStream.Mode =3
        tStream.Open
        Data_5xsoft.Position = iInfoEnd
        Data_5xsoft.CopyTo tStream,iFormStart-iInfoEnd-3
        tStream.Position = 0
        tStream.Type = 2
        tStream.Charset ="gb2312"
     sFormvalue = tStream.ReadText
     tStream.Close
        if objForm.Exists(sFormName) then
         objForm(sFormName)=objForm(sFormName)&", "&sFormvalue        
        else
         objForm.Add sFormName,sFormvalue
        end if
    end if
    iFormStart=iFormStart+iStart+1
    wend
RequestData=""
set tStream =nothing
End Sub

Private Sub Class_Terminate
if Request.TotalBytes>0 then
    objForm.RemoveAll
    objFile.RemoveAll
    set objForm=nothing
    set objFile=nothing
    Data_5xsoft.Close
    set Data_5xsoft =nothing
end if
End Sub


Private function GetFilePath(FullPath)
If FullPath <> "" Then
GetFilePath = left(FullPath,InStrRev(FullPath, "\"))
Else
GetFilePath = ""
End If
End function

Private function GetFileName(FullPath)
If FullPath <> "" Then
GetFileName = mid(FullPath,InStrRev(FullPath, "\")+1)
Else
GetFileName = ""
End If
End function
End Class

Class FileInfo
dim FormName,FileName,FilePath,FileSize,FileType,FileStart
Private Sub Class_Initialize
FileName = ""
FilePath = ""
FileSize = 0
FileStart= 0
FormName = ""
FileType = ""
End Sub

Public function SaveAs(FullPath)
dim dr,ErrorChar,i
SaveAs=true
if trim(fullpath)="" or FileStart=0 or FileName="" or right(fullpath,1)="/" then exit function
set dr=CreateObject("Adodb.Stream")
dr.Mode=3
dr.Type=1
dr.Open
Data_5xsoft.position=FileStart
Data_5xsoft.copyto dr,FileSize
dr.SaveToFile FullPath,2
dr.Close
set dr=nothing
SaveAs=false
end function
End Class
</SCRIPT>

你这组件是什么版的，有的主机对中文支持不好，可能会有编码上的问题
可以下载一下新的组件试试。