C#

private long DigBinary(string file, string strToDig)
        {
            FileStream fs = null;

            char[] chAim = strToDig.ToCharArray();
            char chTemp = '0';
            long latestHitBeginningLocation = 0;
            int locationInArray = 0;

            try { fs = new FileStream(file, FileMode.Open, FileAccess.Read); }
            catch { throw new Exception("An error occured while creating the stream."); }

            try
            {
                while (locationInArray < chAim.Length)
                {
                    chTemp = (char)fs.ReadByte();

                    if( chTemp != chAim[locationInArray] )
                        locationInArray = 0;

                    if (chTemp == chAim[locationInArray])
                    {
                        if (locationInArray == 0)
                            latestHitBeginningLocation = fs.Position - 1;

                        if (locationInArray == chAim.Length)
                            break;

                        locationInArray++;
                    }
                    else
                    {
                        locationInArray = 0;
                        latestHitBeginningLocation = 0;
                    }
                }
            }
            catch { throw new Exception("An error occured while reading the file."); }
            finally { if (fs != null) { fs.Close(); fs.Dispose(); } }

            return latestHitBeginningLocation;
        }