abstarct class BaseClass{
    private bool _disposed = false
 
    protected virtual void Dispose(bool disposing){
        if(_disposed){
            return;
        }
        if(!disposing){
            //Free managed objects
        }
        //Free any other objects
        _disposed = true;
    }
}

class ImplClass : BaseClass{
    private bool _disposed = false;
 
    protected override void Dispose(bool disposing){
        if(_disposed){
            return;
        }
        if(disposing){
            //Free managed objects
        }
        //Free any other objects
        _disposed = true;
        base.Dispose(disposing);
    }
}