ДЗ Кадровый учет

using System;

namespace CSLight
{
    internal class Program
    {
        static void Main(string[] args)
        {
            const string CommandAddDossier = "1";
            const string CommandDeleteDossier = "2";
            const string CommandShowDossier = "3";
            const string CommandFindDossier = "4";
            const string CommandShowAllDossiers = "5";
            const string CommandExit = "exit";

            string[] employeesFullNames = { "Тетерюк Антон", "Пупкин Вася", "Пупкин Петя" };
            string[] employeesJobs = { "Аниматор", "Программист", "Программист" };

            bool isRunnig = true;

            while (isRunnig)
            {
                Console.WriteLine($" {CommandAddDossier} - Добавить досье " +
                    $"\n {CommandDeleteDossier} - Удалить досье" +
                    $"\n {CommandShowDossier} - Найти досье по ID" +
                    $"\n {CommandFindDossier} - Найти досье по фамилии" +
                    $"\n {CommandShowAllDossiers} - Вывести все досье" +
                    $"\n {CommandExit} - Выход");

                string userInput = Console.ReadLine();

                switch (userInput)
                {
                    case CommandAddDossier:
                        AddDossier(ref employeesFullNames, ref employeesJobs);
                        break;

                    case CommandDeleteDossier:
                        DeleteDossier(ref employeesFullNames, ref employeesJobs);
                        break;

                    case CommandShowDossier:
                        FindDossierById(employeesFullNames, employeesJobs);
                        break;

                    case CommandFindDossier:
                        FindDossierBySurname(employeesFullNames, employeesJobs);
                        break;

                    case CommandShowAllDossiers:
                        ShowAllDossiers(employeesFullNames, employeesJobs);
                        break;

                    case CommandExit:
                        isRunnig = false;
                        break;
                }
            }

            Console.ReadKey();
        }

        private static void ShowDossier(int id, string fullName, string job)
        {
            Console.WriteLine($"{id} - {fullName} - {job}");
        }

        private static void ShowAllDossiers(string[] employeesFullNames, string[] employeesJobs)
        {
            for (int i = 0; i < employeesFullNames.Length; i++)
            {
                ShowDossier(i, employeesFullNames[i], employeesJobs[i]);
            }
        }

        private static void FindDossierBySurname(string[] employeesFullNames, string[] employeesJobs)
        {
            Console.WriteLine("Введите фамилию сотрудника:");
            string employeSurname = Console.ReadLine();
            char surnameSeparator = ' ';
            int surnamePosition = 0;
            bool isSurnaneExist = false;

            for (int i = 0; i < employeesFullNames.Length; i++)
            {
                string[] tempArray = employeesFullNames[i].Split(surnameSeparator);

                if (employeSurname == tempArray[surnamePosition])
                {
                    isSurnaneExist = true;
                    ShowDossier(i, employeesFullNames[i], employeesJobs[i]);
                }
            }

            if (isSurnaneExist == false)
            {
                Console.WriteLine("Сотрудник с такой фамилией не найден");
            }
        }

        private static void FindDossierById(string[] employeesFullNames, string[] employeesJobs)
        {
            int employeId;
            Console.WriteLine("Введите ID сотрудника:");

            if (TryFindId(out employeId, Console.ReadLine(), employeesFullNames.Length - 1))
            {
                ShowDossier(employeId, employeesFullNames[employeId], employeesJobs[employeId]);
            }
        }

        private static void DeleteDossier(ref string[] employeesFullNames, ref string[] employeesJobs)
        {
            Console.WriteLine("Введите ID");

            if (TryFindId(out int employeId, Console.ReadLine(), employeesFullNames.Length - 1))
            {
                DecreaseArraySize(ref employeesFullNames, employeId);
                DecreaseArraySize(ref employeesJobs, employeId);
            }
        }

        private static void AddDossier(ref string[] employeesFullNames, ref string[] employeesJobs)
        {
            Console.WriteLine("Введите ФИО сотрудника:");

            string employeInfo = Console.ReadLine();
            IncreaseArraySize(ref employeesFullNames, employeInfo);

            Console.WriteLine("Введите должность сотрудника:");

            employeInfo = Console.ReadLine();
            IncreaseArraySize(ref employeesJobs, employeInfo);
        }

        private static void IncreaseArraySize(ref string[] array, string info)
        {
            int numberToIncrease = 1;
            int newSize = array.Length + numberToIncrease;

            string[] tempArray = new string[newSize];

            for (int i = 0; i < newSize; i++)
            {
                if (i < array.Length)
                {
                    tempArray[i] = array[i];
                }
            }

            tempArray[tempArray.Length - 1] = info;
            array = tempArray;
        }

        private static void DecreaseArraySize(ref string[] array, int startShift)
        {
            int numberToDecrease = 1;
            int newSize = array.Length - numberToDecrease;
            string[] tempArray = new string[newSize];

            for (int i = startShift; i < array.Length - 1; i++)
            {
                array[i] = array[i + 1];
            }

            for (int i = 0; i < newSize; i++)
            {
                if (i < array.Length)
                {
                    tempArray[i] = array[i];
                }
            }

            array = tempArray;
        }

        private static bool TryFindId(out int employeId, string userInput, int maxIndex)
        {
            if (int.TryParse(userInput, out employeId) && employeId <= maxIndex && employeId >= 0)
            {
                return true;
            }
            Console.WriteLine("ID не найден");
            return false;
        }
    }
}