' This example compresses data in the GZip format
' from a file to memory in 8K (8192 byte) chunks. 

Const CHUNKSIZE = 8192

Dim xCompress As New XceedStreamingCompression

Call xCompress.License( "your license key" ) 

Dim lOffSet As Long
Dim lFileSize As Long
Dim vaBytesRead As Variant
Dim vaCompressed As Variant 

Set xCompress.CompressionFormat = New XceedGZipCompressionFormat 

lOffSet = 0 ' We must track the current offset 

On Error Resume Next 

lFileSize = FileLen("c:\temp\source.txt")

While lOffSet < lFileSize
  'bEndOfData will be true if the current offset + CHUNKSIZE exceeds the 
  'end of the file. 
  vaCompressed = xCompress.ReadFile("c:\temp\source.txt", lOffSet, CHUNKSIZE, cfpCompress, _
                                    (lOffSet + CHUNKSIZE >= lFileSize), vaBytesRead)  

  If Not IsEmpty(vaCompressed) Then 
    ' You now have a portion of compressed data you can use. 
    ' For example, transfer it, process it, etc. 
  End If  

  lOffSet = lOffSet + vaBytesRead 
Wend 

If Err.Number = 0 Then
  MsgBox "Finished compressing file to memory." 
Else
  MsgBox Err.Number & " " & Err.Description 
End If