public interface ICommand
    {
        string LogIn(string data);
        string GetChars(string data);
    }

public class Commands : ICommand
    {
        public string LogIn(string data)
        {
            TableManager tableManager = new TableManager();
            User user = new User();
            var logpass = Separator.Data;
            var chars = tableManager.GetTableInfo("*", "Chars", 1);
            string reply;
            if (user.loggedin(logpass[0], logpass[1]))
            {
                reply = "Пользователь существует. Список персонажей: " + chars;
            }
            else
            {
                reply = "Такого пользователя не существует!";
            }
            return reply;
        }

        public string GetChars(string data)
        {
            return "хуй" + data;
        }
    }

    public class CommandDictionary
    {
        private ICommand _commands;
        private Dictionary<string, Func<string, string>> _dictionary;

        public CommandDictionary(ICommand commands)
        {
            _commands = commands;
            _dictionary = CreateDictionary();
        }
        public Dictionary<string, Func<string, string>> CreateDictionary()
        {
            var dictionary = new Dictionary<string, Func<string, string>>
            {
                {"LogIn", _commands.LogIn},
                {"GetChars", _commands.GetChars}
            };
            return dictionary;
        }

        public string RunCommand(string name, string value)
        {
            if (_dictionary.ContainsKey(name))
            {
                return _dictionary[name].Invoke(value);
            }
            return string.Empty;
        }
    }