public class BetterDisposableClass : IDisposable {

  private bool disposed = false;

  public void Dispose() {
    if (disposed) return;
    CleanUpManagedResources();
    CleanUpNativeResources();
    GC.SuppressFinalize(this);
    disposed = true;
  }

  public void ImportantOperation() {
    if (disposed) throw new ObjectDisposedException();
    // ...
  }

  protected virtual void CleanUpManagedResources() {
    // ...
  }
  protected virtual void CleanUpNativeResources() {
    // ...
  }

  ~BetterDisposableClass() {
    CleanUpNativeResources();
  }

}