解析Nginx日志

NginxLogParser

    public class NginxLogParser
    {
        /// <summary>
        ///     解析Nginx日志
        /// </summary>
        /// <param name="log"></param>
        /// <returns></returns>
        /// <remarks>
        ///     \x0A*,\x08\xD4\x98\x82*\xFF
        ///     拆分为：
        ///     0x0A
        ///     *
        ///     ,
        ///     0x08
        ///     0xD4
        ///     0x98
        ///     0x82
        ///     *
        ///     0xFF
        /// </remarks>
        public byte[] Parse(string log)
        {
            using (var ms = new MemoryStream())
            {
                var state = 0;
                /*
                 * 0:开始
                 * 1:转义符
                 * 2:x
                 * 3:第一个数据位
                 * 4:第二个数据位
                 */
                var buffer = new char[2];
                foreach (var code in log)
                {
                    switch (state)
                    {
                        case 0:
                        {
                            if (code == '\\')
                            {
                                state = 1;
                            }
                            else
                            {
                                ms.WriteByte((byte) code);
                            }
                        }
                            break;
                        case 1:
                        {
                            if (code == 'x')
                            {
                                state = 2;
                            }
                            else
                            {
                                throw new Exception("格式不正确");
                            }
                        }
                            break;
                        case 2:
                        {
                            buffer[0] = code;
                            state = 3;
                        }
                            break;
                        case 3:
                        {
                            buffer[1] = code;
                            ms.WriteByte(Convert.ToByte(new string(buffer), 16));
                            state = 0; //归零状态机
                        }
                            break;
                    }
                }
                return ms.ToArray();
            }
        }
    }