VB 6.0 Binary Reading and Writing from VB.NET - vb.net

Question

I have a vb.net code and want to convert it in vb 6.0. But I have some difficulties. I cant find equivalent of some .net classes
Dim byteswritten As Integer
Dim fs As System.IO.FileStream
Dim r As System.IO.BinaryReader
Dim CHUNK_SIZE As Integer = 65554
fs = New System.IO.FileStream(filePath, System.IO.FileMode.Open, System.IO.FileAccess.Read)
r = New System.IO.BinaryReader(fs)
Dim FSize As Integer = CType(fs.Length, Integer)
Dim chunk() As Byte = r.ReadBytes(CHUNK_SIZE)
While (chunk.Length > 0)
dmPutStream.Write(chunk, chunk.Length, byteswritten)
If (FSize < CHUNK_SIZE) Then
CHUNK_SIZE = FSize
chunk = r.ReadBytes(CHUNK_SIZE)
Else
chunk = r.ReadBytes(CHUNK_SIZE)
End If
End While
Well, the document can be big then we used chunk. But I dont know steps for vb 6.0
Such as what i should do for binary reading.

Answer 1

Without all your code for opening the write stream and closing the read and write streams, here's an example of how you can do it in VB6 using ADODB.Stream.
Under Project | References, add a reference to ADO Active X Data Objects Library. My version is 6.1, but you should be okay to just choose the latest version - depends on what version of ADO is installed on your system
Hope it helps - more info online if you want to look at all the ADODB.Stream methods and properties
Public Sub StreamData(strWriteFilename As String, filePath As String)
Const CHUNK_SIZE As Long = 65554
Dim byteswritten As Integer
Dim FSize As Long
Dim adofs As New ADODB.Stream 'Object 'System.IO.FileStream
Dim varData As Variant
' Include this here - but probably defined elsewhere
Dim dmPutStream As New ADODB.Stream
' Open Write Stream
' *** Looks like you do this elsewhere
Set dmPutStream = CreateObject("ADODB.Stream")
With dmPutStream
.Type = adTypeBinary
.Open strWriteFilename, adModeWrite
End With
' Open Read strema and start pushing data from it to the write stream
Set adofs = CreateObject("ADODB.Stream") 'New System.IO.FileStream(filePath, System.IO.FileMode.Open, System.IO.FileAccess.Read)
With adofs
.Type = adTypeBinary
.Open
.LoadFromFile filePath
' Size of Read file - do you want this?
FSize = .Size
varData = .Read(CHUNK_SIZE)
Do While Len(varData) > 0
dmPutStream.Write varData
If Not .EOS Then
varData = .Read(CHUNK_SIZE)
End If
Loop
.Close
End With
'Save binary data To disk
dmPutStream.SaveToFile strWriteFilename, adSaveCreateOverWrite
dmPutStream.Close
End Sub

Answer 2

Converting VB.NET to VB6 is a bad idea, and completely unnecessary. If you need to use the VB.NET code from a VB6 application, the best thing to do would be to create a COM-visible wrapper for your .NET library, and call that wrapper from your VB6 application.
You probably CAN convert the code functionally with VB6, but there really is no point. VB.NET is a better language than VB6, use its COM capabilities to save you from writing endless sketchy VB6 code.
If you are dead set on doing this, you will need to reproduce the Stream and Reader classes functionally.
Here is the source for FileStream.cs:
http://referencesource.microsoft.com/#mscorlib/system/io/filestream.cs
And for BinaryReader:
http://referencesource.microsoft.com/#mscorlib/system/io/binaryreader.cs