System.Data.Common.DBConnectionString.ParseRestrictions C# (CSharp) Method

        private static string[] ParseRestrictions(string restrictions, Hashtable synonyms)
        {
#if DEBUG
            DataCommonEventSource.Log.Trace("<comm.DBConnectionString|INFO|ADV> Restrictions='{0}'", restrictions);
#endif
            List<string> restrictionValues = new List<string>();
            StringBuilder buffer = new StringBuilder(restrictions.Length);

            int nextStartPosition = 0;
            int endPosition = restrictions.Length;
            while (nextStartPosition < endPosition)
            {
                int startPosition = nextStartPosition;

                string keyname, keyvalue; // since parsing restrictions ignores values, it doesn't matter if we use ODBC rules or OLEDB rules
                nextStartPosition = DbConnectionOptions.GetKeyValuePair(restrictions, startPosition, buffer, false, out keyname, out keyvalue);
                if (!string.IsNullOrEmpty(keyname))
                {
#if DEBUG
                    DataCommonEventSource.Log.Trace("<comm.DBConnectionString|INFO|ADV> KeyName='{0}'", keyname);
#endif
                    string realkeyname = ((null != synonyms) ? (string)synonyms[keyname] : keyname);
                    if (string.IsNullOrEmpty(realkeyname))
                    {
                        throw ADP.KeywordNotSupported(keyname);
                    }
                    restrictionValues.Add(realkeyname);
                }
            }
            return RemoveDuplicates(restrictionValues.ToArray());
        }