C# CRC-16数据校验

//低位在前高位在后
public static byte[] CRC16LowHigh(IList<byte> data, int offset, int length)
{
int count = data.Count;
if (count > 0 && offset + length <= count)
{
ushort num = 0xFFFF;
ushort val = 0x8408;//根据校验规则不一样，参数值设置不一样,通用值【0xA001】
for (int i = 0; i < length; i++)
{
num = (ushort)(num ^ data[offset + i]);
for (int j = 0; j < 8; j++)
{
num = ((((uint)num & (true ? 1u : 0u)) != 0) ? ((ushort)((uint)(num >> 1) ^ val)) : ((ushort)(num >> 1)));
}
}
byte b = (byte)(num & 0x00FF);
byte b2 = (byte)((num & 0xFF00) >> 8);
return new byte[2] { b, b2 };
}
return new byte[2];
}