上传|无组件

    关于无组件文件上传的文章已经很多了，所以在这里我不想再解释无组件文件上传的原理。在ASP中无法将二进制文件数据直接保存成文件，所以我们一般还是利用数据库来保存用户上传的文件。

1。数据库表结构(Access)：
UserID:Text(保存上传文件的用户ID)
FileContentType:Text(用来保存上传文件的类型，eg:"Application/msword"，主要用来使用户能正确下载此文件）
FileContent:OLE Object（保存文件数据）

2。HTML文件
muploadfile.htm
<Form name="upload_file" enctype="multipart/form-data" action="muploadfile.asp" method=post>
<input type=hidden name="UserID" value="abc">
<input type=hidden name="FileUploadStart"> '这里用来表示开始文件数据上传
File to send:

<INPUT TYPE="file" name="file_up" size="30">

<INPUT TYPE="file" name="file_up" size="30">

<input type=hidden name="FileUploadEnd"> '这里用来表示文件数据结束
<input type=submit value=Submit>
</Form>

3。ASP文件
muploadfile.asp

<%
Response.Expires=0
Function bin2str(binstr)
Dim varlen,clow,ccc,skipflag

skipflag=0
ccc = ""
If Not IsNull(binstr) Then
varlen=LenB(binstr)
For i=1 To varlen
If skipflag=0 Then
clow = MidB(binstr,i,1)
If AscB(clow) > 127 Then
ccc =ccc & Chr(AscW(MidB(binstr,i+1,1) & clow))
skipflag=1
Else
ccc = ccc & Chr(AscB(clow))
End If
Else
skipflag=0
End If
Next
End If
bin2str = ccc
End Function

varByteCount = Request.TotalBytes
bnCRLF = chrB( 13 ) & chrB( 10 )
binHTTPHeader=Request.BinaryRead(varByteCount)
Divider = LEFTB( binHTTPHeader, INSTRB( binHTTPHeader, bnCRLF ) - 1 )

'开始读非文件域的数据
Do while lenB(binHTTPHeader)>46

binHeaderData = LeftB(binHTTPHeader, INSTRB( binHTTPHeader, bnCRLF & bnCRLF )-1)
strHeaderData=bin2str(binHeaderData)

lngFieldNameStart=Instr(strHeaderData,"name="&chr(34))+Len("name="&chr(34))
lngFieldNameEnd=Instr(lngFieldNameStart,strHeaderData,chr(34))


strFieldName=Mid(strHeaderData,lngFieldNameStart,lngFieldNameEnd-lngFieldNameStart)
strFieldName=Trim(strFieldName)
strFieldName=Replace(strFieldName,vbcrlf,vbnullstring)

'判断文件数据时候开始
If strComp(strFieldName,"FileUploadStart",1)=0 Then
binHTTPHeader=MIDB(binHTTPHeader,INSTRB( DataStart + 1, binHTTPHeader, divider ))
exit do
End if

DataStart = INSTRB( binHTTPHeader, bnCRLF & bnCRLF ) + 4
DataEnd = INSTRB( DataStart + 1, binHTTPHeader, divider ) - DataStart

binFieldValue=MIDB( binHTTPHeader, DataStart, DataEnd )
strFieldValue=bin2str(binFieldValue)
strFieldValue=Trim(strFieldValue)
strFieldValue=Replace(strFieldValue,vbcrlf,vbnullstring)

'非文件上传域变量赋值
execute strFieldName&"="""&strFieldValue&""""


binHTTPHeader=MIDB(binHTTPHeader,INSTRB( DataStart + 1, binHTTPHeader, divider ))

loop

'开始处理文件数据
Do while lenB(binHTTPHeader)>46


binHeaderData = LeftB(binHTTPHeader, INSTRB( binHTTPHeader, bnCRLF & bnCRLF )-1)

strHeaderData=bin2str(binHeaderData)

'读取上传文件的Content-Type
lngFileContentTypeStart=Instr(strHeaderData,"Content-Type:")+Len("Content-Type:")
strFileContentType=Trim(Mid(strHeaderData,lngFileContentTypeStart))
strFileContentType=Replace(strFileContentType,vbCRLF,vbNullString)

'读取上传的文件名
lngFileNameStart=Instr(strHeaderData,"filename="&chr(34))+Len("filename="&chr(34))
lngFileNameEnd=Instr(lngFileNameStart,strHeaderData,chr(34))
strFileName=Mid(strHeaderData,lngFileNameStart,lngFileNameEnd-lngFileNameStart)
strFileName=Trim(strFileName)
strFileName=Replace(strFileName,vbCRLF,vbNullString)

'读取上传文件数据
DataStart = INSTRB( binHTTPHeader, bnCRLF & bnCRLF ) + 4
DataEnd = INSTRB( DataStart + 1, binHTTPHeader, divider ) - DataStart

If strFileName<>"" Then

binFieldValue=MIDB( binHTTPHeader, DataStart, DataEnd )

'将上传的文件写入数据库
set conn = Server.CreateObject("ADODB.Connection")
conn.Open "DSN=abc"

SQL="select * from User_File"
set rs=server.CreateObject("ADODB.Recordset")
rs.Open sql,conn,3,3
rs.addnew
rs("UserID")=UserID
rs("FileContentType")=strFileContentType
rs("FileContent").AppendChunk binFieldValue
rs.update
rs.close
set rs=Nothing
conn.Close
set conn=Nothing

End if

binHTTPHeader=MIDB(binHTTPHeader,INSTRB( DataStart + 1, binHTTPHeader, divider ))

loop
%>

4。下载用户上传的文件
<%
Response.Buffer = true
Response.Clear

UserID=request("UserID")

Set conn=server.createobject("adodb.connection")
set rs=server.createobject("adodb.recordset")
conn.open "DSN=UploadFile"
rs.open "select * from User_File where UserID='"&UserID&"'",conn,3,3
Response.ContentType = rs("FileContentType")

lngOffset=0
conChunkSize=1024
lngPictSize=rs("FileContent").ActualSize
Do While lngOffset < lngPictSize
varChunk = rs("FileContent").GetChunk(conChunkSize)
Response.BinaryWrite varChunk
lngOffset = lngOffset + conChunkSize
If lngOffset > lngPictSize Then Exit Do
Loop

rs.close
set rs=Nothing
conn.close
set conn=nothing
%>

就是这些了，希望此方法对大家能有所帮助。：）