BigEndianCodec.putLong(_saltBytes, 0, SecureRandomUtil.nextLong())似乎是生成一个随机的8字节值并将其写入数组(按Big Endian顺序；但是它是随机的，因此不会没关系)".

BigEndianCodec.putLong(_saltBytes, 0, SecureRandomUtil.nextLong()) Seems to be "Generate a random 8-byte value and write it into an array (in Big Endian order; but it's random, so that doesn't matter)".

所以你想要

using (RandomNumberGenerator csprng = RandomNumberGenerator.Create())
{
    csprng.GetBytes(salt);
}

在分配salt并将其传递给Rfc2898DeriveBytes'ctor之间.

Between allocating salt and passing it to Rfc2898DeriveBytes' ctor.