//單一類的實現class MyClass : IDisposable {  public MyClass(){}   ~MyClass()   {    // In case the client forgets to call    // Dispose , destructor will be invoked for    Dispose(false);   }   protected virtual void Dispose(bool disposing)   {    if (disposing)    {     // Free managed objects.    }    // Free unmanaged objects   }   public void Dispose()   {    Dispose(true);    // Ensure that the destructor is not called    GC.SuppressFinalize(this);   } }