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Convert a stream to a byte array

De cate ori nu v-ati lovit de cerinta urmatoare:
Sa se converteasca un stream intr-un sir de bytes.
Am vazut diferite implementari la aceasta solutie. Cea mai comuna este cea in care se itereaza prin stream.
byte[] bytes = new byte[10000];
int temp;
int offset;
while ((temp = ms.Read(bytes, offset, bytes.Length - offset)) > 0)
{
     offset += temp;
}
Aceasta solutie o sa functioneze, dar putem sa ne folosim si de alte functii, care sa simplifice putin codul si sa eliminam sansele ca un bug sa apara.
O alta varianta este sa folosim metoda GetBuffer. Aceasta ne returneaza sirul de bytes din care a fost creat streamul. Trebuie avut grija la doua lucruri aici:
  1. nu se face o copie a sirului de bytes
  2. lungimea sirului care ne este returnat nu reprezinta lungimea reala a streamului. De exemplu daca avem un stream de 10 bytes si apelam GetBuffer, o sa ne fie returnat un sir de lungime 256 din care 246 de elemente nu sunt folosite.
byte[] bytes = ms.GetBuffer();
Ultima solutie pe care o propun, este sa apelam metoda ToArray(). Prin acest mod o sa ne fie returnat un sir de lungime egala cu numarul de bytes din stream si totodata se genereaza o copie a sirului original. Nu trebuie sa ne facem griji ce se intampla daca continutul stream-ului se modifica. Trebuie stiut ca nu conteaza daca din stream s-a facut citire sau nu, ToArray() ne va returna tot sirul de bytes, indiferent de pozitia cursorului.
MemoryStream ms = new MemoryStream(new byte[]{0,1,2,3,4});
var toArray1 = ms.GeArray(); // Lungime sir returnat = 5
ms.ReadByte()
var toArray2 = ms.GeArray(); // Lungime sir tot returnat = 5

Enjoy!

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