[2.0.] Comprimir un fichero con GZip

Imports System.IO
Imports System.IO.Compression

    Public Function compressFile(ByVal pathSource As String, ByVal pathDestination As String) As Boolean
        ' pathSource: path completo del fichero a comprimir
        ' pathDestination: path completo del fichero final comprimido
        Try
            Dim myFileStream As New FileStream(pathSource, FileMode.Open)
            Dim myBuffer(myFileStream.Length) As Byte
 
            ' Lectura de la totalidad del FileStream
            myFileStream.Read(myBuffer, 0, CInt(myFileStream.Length))
            ' cerramos el FileStream
            myFileStream.Close()
            ' creación del fichero que contendrá el fichero comprimido
            myFileStream = New FileStream(pathDestination, FileMode.Create)
            ' compresión de los datos
            Dim myGZipStream As New GZipStream(myFileStream, CompressionMode.Compress, False)
            ' escriobimos los datos comprimidos en el fichero destino
            myGZipStream.Write(myBuffer, 0, myBuffer.Length)
            ' cerramos GZipStream
            myGZipStream.Close()
            Return True
        Catch ex As Exception
            MessageBox.Show(ex.Message)
            Return False
        End Try
    End Function