Silverlight 5 WinRT

  public sealed enum CompressionLevel
  : IComparable, IFormattable, IConvertible
  { Optimal, Fastest, NoCompression }

  public sealed enum CompressionMode
  : IComparable, IFormattable, IConvertible
  { Decompress, Compress }

  public class DeflateStream
  : Stream, IDisposable
  public Stream BaseStream { get; }
  public virtual Boolean CanRead { get; }
  public virtual Boolean CanSeek { get; }
  public virtual Boolean CanWrite { get; }
  public virtual Int64 Length { get; }
  public virtual Int64 Position { get; set; }
  public virtual IAsyncResult BeginRead(Byte array, Int32 offset, Int32 count, AsyncCallback asyncCallback, Object asyncState);
  public virtual IAsyncResult BeginWrite(Byte array, Int32 offset, Int32 count, AsyncCallback asyncCallback, Object asyncState);
  protected virtual void Dispose(Boolean disposing);
  public virtual Int32 EndRead(IAsyncResult asyncResult);
  public virtual void EndWrite(IAsyncResult asyncResult);
  public virtual void Flush();
  public virtual Int32 Read(Byte array, Int32 offset, Int32 count);
  public virtual Int64 Seek(Int64 offset, SeekOrigin origin);
  public virtual void SetLength(Int64 value);
  public virtual void Write(Byte array, Int32 offset, Int32 count);

  public class GZipStream
  : Stream, IDisposable
  public Stream BaseStream { get; }
  public virtual Boolean CanRead { get; }
  public virtual Boolean CanSeek { get; }
  public virtual Boolean CanWrite { get; }
  public virtual Int64 Length { get; }
  public virtual Int64 Position { get; set; }
  public virtual IAsyncResult BeginRead(Byte array, Int32 offset, Int32 count, AsyncCallback asyncCallback, Object asyncState);
  public virtual IAsyncResult BeginWrite(Byte array, Int32 offset, Int32 count, AsyncCallback asyncCallback, Object asyncState);
  protected virtual void Dispose(Boolean disposing);
  public virtual Int32 EndRead(IAsyncResult asyncResult);
  public virtual void EndWrite(IAsyncResult asyncResult);
  public virtual void Flush();
  public virtual Int32 Read(Byte array, Int32 offset, Int32 count);
  public virtual Int64 Seek(Int64 offset, SeekOrigin origin);
  public virtual void SetLength(Int64 value);
  public virtual void Write(Byte array, Int32 offset, Int32 count);