dispose

         class a : IDisposable
        {
                 bool disposed;

                ~a()
                {
                        Dispose( false);
                }

IDisposable 成员 #region IDisposable 成员

                 public void Dispose()
                {
                        Dispose( true);
                        GC.SuppressFinalize( this);
                }

                #endregion

                 protected virtual void Dispose( bool disposing)
                {
                         if (!disposed)
                        {
                                 if (disposing)
                                {

                                }
                                disposed = true;
                        }
                }

                 public void f()
                {
                         if (disposed)
                                 throw new ObjectDisposedException( "this");
                }

                 public void Close()
                {
                        Dispose();
                }
    
        }

         class b : a
        {
                 bool disposed;

                ~b()
                {
                        Dispose( false);
                }

                 protected override void Dispose( bool disposing)
                {
                         try
                        {
                                 if (!disposed)
                                {
                                         if (disposing)
                                        {

                                        }
                                        disposed = true;
                                }
                        }
                         finally
                        {
                                 base.Dispose(disposing);
                        }
                }
        }