Question

there’s two methods i was looking at @stackOverFlow , i guess there might be even more of them
somewhere else , my qusetion is what is the best performance wise

and second question , i have this code that simply takes a couple of byte[]

     bool ArraysEqual(byte[] a1, byte[] a2)
     {
         if (a1 == a2)
             return true;
          if (a1 == null || a2 == null)
             return false;
          if (a1.Length != a2.Length)
             return false;
          for (int i = 0; i < a1.Length; i++)
         {
             if (a1[i] != a2[i])
                 return false;
         }
         return true;
     } 

and i couldn’t implement this one , not kowing the workaroud iguess i’ve used the wrong syntax
so if i have a helper method to read a byet[] file

    public byte[] readByteArr(string FilePath)
    {
       return File.ReadAllBytes(FilePath);

    } 

i could make it simply via 



void CompareIt(){

byte[] src = readByteArr(S.bar);
byte[] dest = readByteArr(D.bar);
if(ArraysEqual(src, dest))
DoSomthing
}

how do i make CompareIt(), with sets of parameters requierd in this Second code i allso try to implement, just to check which performs beeter

    bool ArraysEqual<T>(T[] a1, T[] a2)
    {
     if (ReferenceEquals(a1,a2))
         return true;
      if (a1 == null || a2 == null)
         return false;
      if (a1.Length != a2.Length)
         return false;
      EqualityComparer<T> comparer = EqualityComparer<T>.Default;
     for (int i = 0; i < a1.Length; i++)
     {
         if (!comparer.Equals(a1[i], a2[i]))
            return false;
     }
     return true;
 } 

what is the right syntax to implement this last one, and if there’s a quicker way to compare two

 byte[] 

knowing they’re the same length .
and what do you think about this ?

ReEditing:

the first is unsafe code .

second is first code i wrote (bool ArraysEqual())

and third is

myArray.SequenceEqual(otherArray); 

Now Take A good look at this
please Do allow me to announce, the winner is :

[DllImport("msvcrt.dll", CallingConvention = CallingConvention.Cdecl)]
static extern int memcmp(byte[] b1, byte[] b2, long count);

static bool ByteArrayCompare(byte[] b1, byte[] b2)
{
    // Validate buffers are the same length.     
    // This also ensures that the count does not exceed the length of either buffer.
    return b1.Length == b2.Length && memcmp(b1, b2, b1.Length) == 0;
}

@Chaos . Can u please post the implemetation of Your Random with my Pinvoke ?

Answer 1

if you use .NET > 3.0:

myArray.SequenceEqual(otherArray);

see MSDN – Enumerable.SequenceEqual

if you want to use a custom “EqualityComparer” you can use MSDN – Enumerable.SequenceEqual with IEqualityComparer

😉