This may help - it's VB6 code but should give you an idea. I need to
upgrade it to VB.NET too actually.
It's a function I use for inserting image files into Access - should
work for any binary file. I found a few examples on ms.com and elsewhere
but none of them seemed to work that well. I rewrote the below function
and it seems to work ok.
HTH
'This function updates the first row in a recordset with the passed 'file.
'The recordset should contain the primary key of the record as well as
'the BLOB field otherwise you get a "missing key" error.
Private Const BlockSize = 32000
Function fcnLoadBlobIntoDatabase(SourceFile As String, _
r As Recordset, sField As String) As Boolean
Dim NumBlocks As Integer, F As Integer, i As Integer
Dim FileLength As Long, LeftOver As Long
Dim FileData() As Byte
On Error GoTo Err_ReadBLOB
'open the source file for access
F = FreeFile
Open SourceFile For Binary Access Read As F
' Get the length of the file.
FileLength = LOF(F)
If FileLength = 0 Then Exit Function
' Calculate the number of blocks to read and leftover bytes.
LeftOver = FileLength Mod BlockSize
NumBlocks = (FileLength - LeftOver) \ BlockSize
'Now load read the file in blocks and load into FileData
Do While i <= NumBlocks
'size FileData as per blocksize of the same size
'as the remaining data
If i < NumBlocks Then
ReDim FileData(BlockSize - 1)
Else
ReDim FileData(LeftOver - 1)
End If
'Read the data from the file into FileData
Get F, , FileData
'append to our BLOB field
r(sField).AppendChunk (FileData)
'increment our block counter
i = i + 1
Loop
' Update the record - we're done
r.Update
fcnLoadBlobIntoDatabase = True
Err_ReadBLOB:
r.close
On Error Resume Next
Close F
End Function
And for getting the BLOB out again.
Function fcnGetBlobFromDatabase(r As Recordset, sField As String,
DestinationFile As String) As Boolean
Dim NumBlocks As Integer, F As Integer, i As Integer
Dim FileLength As Long, LeftOver As Long
Dim FileData() As Byte
On Error GoTo Err_WriteBLOB
' Get the size of the field.
FileLength = r(sField).ActualSize
If FileLength = 0 Then Exit Function
' Calculate number of blocks to write and leftover bytes.
LeftOver = FileLength Mod BlockSize
NumBlocks = (FileLength - LeftOver) / BlockSize
' Remove any existing destination file.
F = FreeFile
Open DestinationFile For Output As F
Close F
' Open the destination file.
Open DestinationFile For Binary As F
'Loop through the blob
Do
FileData() = r(sField).GetChunk(BlockSize)
Put F, , FileData()
Loop Until UBound(FileData) < BlockSize - 1
fcnGetBlobFromDatabase = True
Err_WriteBLOB:
On Error Resume Next
Close F
End Function
Stan Smith wrote:
I couldn't decide which newsgroup to post this in so I thought I would start
here.
I can create an "OLE Object" field manually in Microsoft Access and insert
an Excel spreadsheet or a Word document, etc. into the field.
I would like to be able to programmatically do the same thing. Basicaly I
want to be able to add and retrieve and reconstitute Excel spreadsheets and
Word documents, etc. I don't need to be able to programmatically create the
Access database and I'm pretty sure that I can do that with other code I
have already written.
Can someone point me in the right direction? I have already looked at the
following link and while I have a little experience with C++ it would be
much more preferable to write the app in VB.NET.
http://www.codeguru.com/Cpp/data/mfc...icle.php/c1123
Thanks.
Stan
Stan Smith
ACT! Certified Consultant
ADS Programming Services
2320 Highland Avenue South
Suite 290
Birmingham, AL 35205
205-222-1661
www.adsprogramming.com
ssmith_at_adsprogramming.com
