BF2Statistics.Gamespy.MasterClient.IsOperator C# (CSharp) Method

        private static bool IsOperator(string filter, int i, out int length, bool previous = false)
        {
            bool isOperator = false;
            length = 0;

            if (i < filter.Length - 1)
            {
                string op = filter.Substring(i - (i >= 2 ? (previous ? 2 : 0) : 0), 1);
                if (op == "=" || op == "<" || op == ">")
                {
                    isOperator = true;
                    length = 1;
                }
            }

            if (!isOperator)
            {
                if (i < filter.Length - 2)
                {
                    string op = filter.Substring(i - (i >= 3 ? (previous ? 3 : 0) : 0), 2);
                    if (op == "==" || op == "!=" || op == "<>" || op == "<=" || op == ">=")
                    {
                        isOperator = true;
                        length = 2;
                    }
                }
            }

            if (!isOperator)
            {
                if (i < filter.Length - 4)
                {
                    string op = filter.Substring(i - (i >= 5 ? (previous ? 5 : 0) : 0), 4);
                    if (op.Equals("like", StringComparison.InvariantCultureIgnoreCase))
                    {
                        isOperator = true;
                        length = 4;
                    }
                }
            }

            if (!isOperator)
            {
                if (i < filter.Length - 8)
                {
                    string op = filter.Substring(i - (i >= 9 ? (previous ? 9 : 0) : 0), 8);
                    if (op.Equals("not like", StringComparison.InvariantCultureIgnoreCase))
                    {
                        isOperator = true;
                        length = 8;
                    }
                }
            }

            return isOperator;
        }