C# - Bitmap in base64 codierten String wandeln

/// <summary>
/// Wandelt eine Bitmap in einen Base64 codierten String um.
/// benötigte Namespaces:
/// System.Drawing.Imaging
/// System.IO
/// </summary>
/// <param name="image">die zu codierende Bitmap</param>
/// <returns>der base64 codierte String</returns>
private string BitmapToBase64(Image image)
{            
    MemoryStream memory = new MemoryStream();
    image.Save(memory, ImageFormat.Bmp);
    string base64 = Convert.ToBase64String(memory.ToArray());
    memory.Close();
    memory.Dispose();
    return base64;
}