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Tuplu in C#, am luat taurul de coarne

Ce este un tuplu? Este o metoda de a grupa elemente de tipuri diferite. Apare mai ales in cadrul limbajelor funcționale sau dinamice precum Python.
De exemplu daca trebuie sa stocam coordonatele unui punct in spatiu putem sa avem (12,"C",23.3m). Fiecare axa poate sa aiba o unitate de masura diferita.
In C# 4.0 avem o clasa statica ajutatoare denumita Tuple, care ne ofera posibilitatea sa cream un tuplu cu pana la 8 tipuri generice( Tuple.Create(T1,..,T8) ).
Pentru exemplul de mai sus ar trebui sa avem urmatorul obiect:
var point=Tuple.Create<int,string,decimal)(12,"C",23.3m)

Daca vrem sa cream un tuplu care sa contina 23.3m si 40m pe axa 0z atunci putem sa cream un nou tuplu pe pozitia a 3-a.
var point=Tuple.Create(12,"C",new Tuple<decimal,decimal>(23.3m,40m)

Prin aceasta modalitate putem sa stocam coordonatele unor forme geometrice.
In cazul in care ajungem sa avem nevoie de un Tuplu cu mai mult de opt elemente generice atunci putem pe ultima pozitie definim un nou tuplu. Pentru a ne face munca mai usoara, ne putem defini niste clase ajutatoare care sa ne ofere tupluri de 9,10 sau n dimensiuni. Din pacate nu putem sa extindem metoda Create deoarece nu putem scrie extension method pentru metodele statice.
Atentie, nu putem itera un tuplu. Putem sa accesam fiecare element a unui tuplu prin proprietatile: Item1, Item2, ... , Item8.
Un tuplu se poate folosi ca un tip de data ajutator cand trebuie sa stocam temporar anumite date care nu au o legatura directa intre ele. Poate sa fie folosit cu succes cand vrem sa inlocuim clasele temporare folosite pentru a obtine de la DAL pentru a le trasmite spre UX sau orice rezultat care returneaza mai multe valori.


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