Home work - find criminal

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Home_Work
{
    class Program
    {
        static void Main()
        {
            DataBase dataBase = new DataBase();
            dataBase.Work();
        }
    }

    class DataBase
    {
        private List<Criminal> _criminals;

        public DataBase()
        {
            _criminals = new List<Criminal>();
            FillDataBase();
        }

        public void Work()
        {
            bool isWorking = true;
            List<Criminal> criminals = _criminals;
            int number;

            while(isWorking == true)
            {
                ShowSelection(criminals);
                Console.WriteLine("1. Отфильтровать.\n2. Показать всех.\n3. Выход.");
                Console.Write("Введите команду: ");
                number = GetNumber();

                switch (number)
                {
                    case 1:
                        criminals = FilterOutCriminals();
                        break;

                    case 2:
                        criminals = _criminals;
                        break;

                    case 3:
                        isWorking = false;
                        break;

                    default:
                        Console.WriteLine("Неверная команда.");
                        break;
                }

                Console.ReadKey();
                Console.Clear();
            }
        }

        private List<Criminal> FilterOutCriminals()
        {
            int height;
            int weight;
            National national;

            Console.Write("Введите рост: ");
            height = GetNumber();

            Console.Write("Введите вес: ");
            weight = GetNumber();

            national = GetNational();

            var filteredCriminals = _criminals.Where(criminal => criminal.Height == height &&
                                                                 criminal.Weight == weight &&
                                                                 criminal.National == national &&
                                                                 criminal.IsArrested == false).ToList();

            return filteredCriminals;
        }

        private int GetNumber()
        {
            bool isConverted = false;
            int number = 0;
            string userInput;

            while(isConverted == false)
            {
                userInput = Console.ReadLine();
                isConverted = Int32.TryParse(userInput, out number);
            }

            return number;
        }

        private National GetNational()
        {
            bool isSelected = false;
            int nationalCount = Enum.GetNames(typeof(National)).Length;
            int number = 0;

            for(int i = 0; i < nationalCount; i++)
            {
                Console.WriteLine($"{i + 1}. {(National)i}.");
            }

            while(isSelected == false)
            {
                number = GetNumber() - 1;

                if (number >= 0 && number < nationalCount)
                {
                    isSelected = true;
                }
                else
                {
                    Console.WriteLine("Введите номер национальности.");
                }
            }

            return (National)number;
        }

        private void ShowSelection(List<Criminal> criminals)
        {
            foreach (Criminal criminal in criminals)
            {
                criminal.ShowInfo();
            }
        }

        private void FillDataBase()
        {
            _criminals.Add(new Criminal("Черёмушко Алексей Алексеевич", National.Russia, 180, 80, false));
            _criminals.Add(new Criminal("Чер Дмитрий Алексеевич", National.Russia, 185, 50, false));
            _criminals.Add(new Criminal("Альанах Алексей Дмитриевич", National.Georgia, 180, 90, true));
            _criminals.Add(new Criminal("Вассерман Анатолий Акашанович", National.UA, 185, 80, true));
            _criminals.Add(new Criminal("Шерлок Ди Холмс", National.Ukraina, 170, 70, false));
            _criminals.Add(new Criminal("Макуночи Но Ипо", National.UA, 210, 75, true));
            _criminals.Add(new Criminal("Грозный Иван Васильевич", National.USA, 180, 80, false));
            _criminals.Add(new Criminal("Борн Дмитрий Анатольевич", National.USA, 190, 90, true));
            _criminals.Add(new Criminal("Навальный Владимир Владиславович", National.Ukraina, 160, 75, false));
            _criminals.Add(new Criminal("Евпатий Калодратий", National.Georgia, 150, 50, false));
            _criminals.Add(new Criminal("Никто", National.Russia, 220, 100, true));
            _criminals.Add(new Criminal("Андерсон Джон Викторович", National.Russia, 180, 70, true));
            _criminals.Add(new Criminal("Самураев Душнила Тёмович", National.Ukraina, 150, 90, false));
        }
    }

    class Criminal
    {
        private string _fullName;
        private National _national;
        private int _height;
        private int _weight;
        private bool _isArrested;

        public Criminal(string fullName, National national, int height, int weight, bool isArrested)
        {
            _fullName = fullName;
            _national = national;
            _height = height;
            _weight = weight;
            _isArrested = isArrested;
        }

        public National National => _national;
        public int Height => _height;
        public int Weight => _weight;
        public bool IsArrested => _isArrested;

        public void ShowInfo()
        {
            string status;

            if(_isArrested == true)
            {
                status = "Арестован";
            }
            else
            {
                status = "Разыскивается";
            }

            Console.WriteLine($"{_fullName}. Национальность: {_national}. Рост: {_height}. Вес: {_weight}. {status}.");
        }
    }

    enum National
    {
        Russia,
        USA,
        UA,
        Georgia,
        Ukraina
    }
}