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Metoda marcata cu abstract si override

O metoda sau o propietate poate sa fie marcata ca abstracta cand aceasta nu contine si implementarea.
O metoda sau o propietate poate sa fie marcata ca override cand vrem sa modificam implementarea si sa oferim o noua implementare pentru un menbru mostenit din clasa de baza.
Pana aici nimic deosebit, OOP pur. Oare putem sa avem o metoda care sa fie marcata atat abstracta cat si override? Raspunsul este DA. Desi pare ciudat, putem sa marcam o metoda cu aceste doua atribute:
public void abstract override DoWork();
Cand putem sa avem acest caz?
Cand avem o clasa abstracta care contine o metoda virtuala.
public abstract Actiune
{
public virtual void DoWork()
{
Console.Write("Actiune1.DoWork");
}
}
Aceasta clasa poate sa fie mostenita de o alta clasa care sa ofere o alta implementare de baza la metoda DoWork.
public abstract Actiune2 : Actiune
{
public abstract override void DoWork();
}
Orice clasa ce va implementa clasa abstracta Actiune2 o sa fie obligata sa ofere o implementare la metoda DoWork(), chiar daca Actiune2 mosteneste din clasa abstracta Actiune1 care ofera o implementare pentru metoda noastra.

Comments

  1. Aha - si la properties pot exista astfel de cazuri, desi arata ciudat: http://blogs.msdn.com/b/ericlippert/archive/2011/02/07/strange-but-legal.aspx

    ReplyDelete

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