[RESOLVED] [2005] GZipStream Decompress

[jmcilhinney]

The second parameter to Read and Write are the offset within the array, not the offset within the file. Every time you read data you want to place it in the array starting from the first element, so that parameter value should be zero every time.

Also, the third parameter to Write is the number of bytes to write. You're trying to write 1024 every time but what if you didn't read 1024 bytes in the first place. I suggest that you change this:

While True
 
                bytesRead = compressedData.Read(buffer, offset, 1024)                           'Attempt a 1K read
 
                If bytesRead = 0 Then                                                           'Fail if no data left
                    Exit While
                End If
 
                outData.Write(buffer, offset, 1024)                                             'Write the 1K to file
 
                offset += bytesRead
                totalBytes += bytesRead
            End While

to somethinglike this:

bytesRead = compressedData.Read(buffer, 0, buffer.Length)
 
While bytesRead > 0
    outData.Write(buffer, 0, bytesRead)
    bytesRead = compressedData.Read(buffer, 0, buffer.Length)
End While

Also, you don't need that Finally block at all. You should get to grips with the Using statement, which will implicitly dispose your objects whether there's an exception thrown or not.