C# 字节数组操作

合并字节数组

 public static byte[] CombineByteArray(byte[][] byteArra)
        {
            System.IO.MemoryStream aMS = new System.IO.MemoryStream();
            byte[] tempBA ;
            for (int i = 0; i < byteArra.Length; i++)
            {
                tempBA = byteArra[i];
                aMS.Write(tempBA, 0, tempBA.Length);
            }

            return aMS.ToArray();
        }

 

 //字节数组截取 32位

public unsafe static byte[] SubByteArray(byte[] src, int begin, int length)
        {
            if (src.Length < begin + length)
                throw new Exception("源数组长度不够。");

            byte[] rT = new byte[length];
            int len = length;
            fixed (byte* pSrc = src, pRt = rT)
            {
                byte *p = pSrc + begin;
                int* i1 = (int*)p;
                int* i2 = (int*)pRt;
                while (len >= 4)
                {
                    *i2++ = *i1++;
                    len -= 4;
                }
                byte* c1 = (byte*)i1;
                byte* c2 = (byte*)i2;
                while (len > 0)
                {
                    *c2++ = *c1++;
                    len--;
                }
            }
            return rT;
        }

// from http://www.pinvoke.net/default.aspx/msvcrt/memcmp.html

C# Signature (x86 and x64):

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

C# Signature (x64 only):

[DllImport("msvcrt.dll")]
static extern int memcmp(IntPtr ptr1, IntPtr ptr2, int count);

C# Unsafe Signature (x64 only):

[DllImport("msvcrt.dll")]
static extern unsafe int memcmp(void* ptr1, void* ptr2, int count);

//Extension Method example
public static class ByteArrayExtensions
{
   [DllImport("msvcrt.dll", CallingConvention=CallingConvention.Cdecl)]
   private static extern int memcmp(byte[] b1, byte[] b2, UIntPtr count);

   public static bool SequenceEqual(this byte[] b1, byte[] b2)
   {
      if (b1 == b2) return true; //reference equality check

      if (b1 == null || b2 == null || b1.Length != b2.Length) return false;

      return memcmp(b1, b2, new UIntPtr((uint)b1.Length)) == 0;
   }
}



//http://www.cplusplus.com/reference/clibrary/cstring/memcmp/
unsafe bool CompareByteArray(byte[] b1, byte[] b2)
{
     fixed (byte* p1 = b1)
     fixed (byte* p2 = b2)
     {
        return memcmp((void*)p1, (void*)p2, b1.Length) == 0;
     }
}