C# CRC8

C# CRC8

C#
///
/// This enum is used to indicate what kind of checksum you will be calculating.
///
public enum CRC8_POLY
{
    CRC8 = 0xd5,
    CRC8_CCITT = 0x07,
    CRC8_DALLAS_MAXIM = 0x31,
    CRC8_SAE_J1850 = 0x1D,
    CRC_8_WCDMA = 0x9b,
};

///
/// Class for calculating CRC8 checksums...
///
public class CRC8Calc {
    private byte[] table = new byte[256];

    public byte Checksum(params byte[] val )
    {
        if(val == null)
            throw new ArgumentNullException("val");

        byte c = 0;

        foreach ( byte b in val )
        {
            c = table[c ^ b];
        }

        return c;
    } 

    public byte[] Table
    {
        get
        {
            return this.table;
        }
        set
        {
            this.table = value;
        }
    }

    public byte[] GenerateTable(CRC8_POLY polynomial)
    {
        byte[] csTable = new byte[256];

        for ( int i = 0; i < 256; ++i )
        {
            int curr = i;

            for ( int j = 0; j < 8; ++j )
            {
                if ((curr & 0x80) != 0)
                {
                    curr = (curr << 1) ^ (int)polynomial;
                }
                else
                {
                    curr <<= 1;
                }
            }

            csTable[i] = (byte)curr;
        }

        return csTable;
    }

    public CRC8Calc(CRC8_POLY polynomial)
    {
        this.table = this.GenerateTable(polynomial);
    }
}
Example

C#
using System;

public class CRC8Test
{
    public static void RunSnippet()
    {
        byte checksum;
        byte[] testVal = new byte[]
        {0xee, 0x01, 0x13, 0x00, 0x06, 0x1c, 0x00, 0x20,  0x1d, 0x00, 0x00};
        CRC8Calc crc_dallas = new CRC8Calc(CRC8_POLY.CRC8_DALLAS_MAXIM);
        checksum = crc_dallas.Checksum(testVal);
        WL(checksum);
        CRC8Calc crc = new CRC8Calc(CRC8_POLY.CRC8_CCITT);
        checksum = crc.Checksum(testVal);
        WL(checksum);
    }

    #region Helper methods

    public static void Main()
    {
        try
        {
            RunSnippet();
        }
        catch (Exception e)
        {
            string error = string.Format
            ("---\nThe following error occurred while executing
                the snippet:\n{0}\n---", e.ToString());
            Console.WriteLine(error);
        }
        finally
        {
            Console.Write("Press any key to continue...");
            Console.ReadKey();
        }
    }

    private static void WL(object text, params object[] args)
    {
        Console.WriteLine(text.ToString(), args);
    }

    #endregion
}