.NET ???? ?? ?? ??

??? ??? ??? ???? ?? ???? ????? ???????. ? ????? ??? ???? ? ?? ??? ???? ??? ??? ?? .NET? ?????? ?????.

??? ??? ?? ??? ??? ? ????

?, ??? ??? ?? CRC? ?? ????? ???? ?? ???? ???? ????. ???? ? ??? ?? ??? ??? ????? ?? ??? ?? ??? ??? ? ????.

.NET ?? ??? ?? ?????

?? .NET ?????? ?? ??? ?? ??? ?????.

• System.Security.Cryptography.MD5: ??? MD5 ???? ?????.
• System.Security.Cryptography.SHA1: ??? SHA1 ???? ?????.
• System.Security.Cryptography.SHA256: ??? SHA256 ???? ?????.
• System.Security.Cryptography.SHA512: ??? SHA512 ???? ?????.

???? ????

??? ?? ????? ? ??? ??? ?? ??? ???? ??? ???? ?? ??? ?? ???? ? ????.

const int BYTES_TO_READ = sizeof(Int64);

static bool FilesAreEqual(FileInfo first, FileInfo second)
{
    if (first.Length != second.Length)
        return false;

    if (string.Equals(first.FullName, second.FullName, StringComparison.OrdinalIgnoreCase))
        return true;

    int iterations = (int)Math.Ceiling((double)first.Length / BYTES_TO_READ);

    using (FileStream fs1 = first.OpenRead())
    using (FileStream fs2 = second.OpenRead())
    {
        byte[] one = new byte[BYTES_TO_READ];
        byte[] two = new byte[BYTES_TO_READ];

        for (int i = 0; i < iterations; i++)
        {
            int read1 = fs1.Read(one, 0, BYTES_TO_READ);
            int read2 = fs2.Read(two, 0, BYTES_TO_READ);

            if (read1 != read2 || !one.SequenceEqual(two))
                return false;
        }
    }

    return true;
}

?? ??? ??

?? ???? ??? ??? ??(?: 100MB ??? ??)? ?? ?? ??? ??? ???? ?? ???? ?? ? ?????? ??? ??? ??? ??????.

• ?? ??: 1063ms
• ???? ??: 3031ms
• ??: 865ms

?? ??? ?? ????? ??? ???? ???? ?? ? ????. ??? ??? ??? ?? ?? ??? ?? ???? ????? ? ? ??? ?? ?? ??? ? ????.

? ??? ??? ? ?? ??? ?? .NET?? ?? ?? ??? ?? ? ?????? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!