Public Function New( _
   ByVal stream As Stream, _
   ByVal mode As CompressionMode _
)

Dim stream As Stream
Dim mode As CompressionMode
 
Dim instance As New GZipStream(stream, mode)

public GZipStream( 
   Stream stream,
   CompressionMode mode
)

public:
GZipStream( 
   Stream^ stream,
   CompressionMode mode
)

using (System.IO.Stream input = System.IO.File.OpenRead(fileToCompress))
{
    using (var raw = System.IO.File.Create(outputFile))
    {
        using (Stream compressor = new GZipStream(raw, CompressionMode.Compress))
        {
            byte[] buffer = new byte[WORKING_BUFFER_SIZE];
            int n;
            while ((n= input.Read(buffer, 0, buffer.Length)) != 0)
            {
                compressor.Write(buffer, 0, n);
            }
        }
    }
}

Dim outputFile As String = (fileToCompress & ".compressed")
Using input As Stream = File.OpenRead(fileToCompress)
    Using raw As FileStream = File.Create(outputFile)
    Using compressor As Stream = New GZipStream(raw, CompressionMode.Compress)
        Dim buffer As Byte() = New Byte(4096) {}
        Dim n As Integer = -1
        Do While (n <> 0)
            If (n > 0) Then
                compressor.Write(buffer, 0, n)
            End If
            n = input.Read(buffer, 0, buffer.Length)
        Loop
    End Using
    End Using
End Using

private void GunZipFile(string filename)
{
    if (!filename.EndsWith(".gz))
        throw new ArgumentException("filename");
    var DecompressedFile = filename.Substring(0,filename.Length-3);
    byte[] working = new byte[WORKING_BUFFER_SIZE];
    int n= 1;
    using (System.IO.Stream input = System.IO.File.OpenRead(filename))
    {
        using (Stream decompressor= new Ionic.Zlib.GZipStream(input, CompressionMode.Decompress, true))
        {
            using (var output = System.IO.File.Create(DecompressedFile))
            {
                while (n !=0)
                {
                    n= decompressor.Read(working, 0, working.Length);
                    if (n > 0)
                    {
                        output.Write(working, 0, n);
                    }
                }
            }
        }
    }
}

Private Sub GunZipFile(ByVal filename as String)
    If Not (filename.EndsWith(".gz)) Then
        Throw New ArgumentException("filename")
    End If
    Dim DecompressedFile as String = filename.Substring(0,filename.Length-3)
    Dim working(WORKING_BUFFER_SIZE) as Byte
    Dim n As Integer = 1
    Using input As Stream = File.OpenRead(filename)
        Using decompressor As Stream = new Ionic.Zlib.GZipStream(input, CompressionMode.Decompress, True)
            Using output As Stream = File.Create(UncompressedFile)
                Do
                    n= decompressor.Read(working, 0, working.Length)
                    If n > 0 Then
                        output.Write(working, 0, n)
                    End IF
                Loop While (n  > 0)
            End Using
        End Using
    End Using
End Sub