Viktor Toman
Profile Answers by Viktor Toman

Mar 31st, 2011

   class ByteArray
   {
   // using jagged array as store
   byte[][] storage;
   // maximum amount of data in block
   const int MAX_BLOCK = 65536;

   public ByteArray(int capacity)
   {
   // number of blocks needed
   int n = (int)Math.Ceiling(capacity / (double)MAX_BLOCK);
   // capacity of last block
   int lastBlock = (n == 1) ? capacity : capacity % MAX_BLOCK;
   // creating storage
   storage = new byte[n][];
   for (int block = 0; block < n; block++)
   if (block == n - 1) // last block custom capacity
   storage[block] = new byte[lastBlock];
   else
   storage[block] = new byte[MAX_BLOCK];
   }

   public byte this[int index]
   {
   get
   {
   int block = index / MAX_BLOCK;
   int element = index % MAX_BLOCK;

   return storage[block][element];
   }
   set
   {
   int block = index / MAX_BLOCK;
   int element = index % MAX_BLOCK;

   storage[block][element] = value;
   }
   }
   }

ByteArray Class

Write a class called ByteArray that implement allocating, reading and writing to an array of bytes. The runtime environment has a limitation. The maximum continuous memory size that it can allocated is 64k bytes. It can allocate many 64K ( or less) chunks.
The ByteArray class should hide this limitation and support allocating arrays larger than 64K as in the following example :

ByteArray ba = new ByteArray (250000); // Create
ba[150000] = 15; // Write byte
byte x = ba[190000]; // Read byte

wailoon.ho
Profile Answers by wailoon.ho Questions by wailoon.ho
Jun 28th, 2010
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Raedon
Profile Answers by Raedon

Jan 25th, 2011

class ByteArray
   {
   private byte[] byteArray;

   public byte this[int index]
   {
   get { return byteArray[Validate(index)]; }
   set { byteArray[Validate(index)] = value; }
   }

   public ByteArray(int lenght)
   {
   byteArray = new byte[Validate(lenght)];
   }

   private int Validate(int lenght)
   {
   int result = lenght;
   if (!((lenght > 0) && (lenght <= 65535)))
   {
   Debug.Fail("The index is out of range.");
   result = 0;
   }
   return result;
   }

   }