ДЗ: Кадровый учет

using System;

internal class Program
{
    static void Main(string[] args)
    {
        const string CommandExit = "Exit";
        const string CommandAddDossier = "1";
        const string CommandShowAllDossier = "2";
        const string CommandRemoveDossier = "3";
        const string CommandSearchByLastName = "4";

        string[] employeeFullNames = { "Сакутин Роман" };
        string[] employeePositions = { "Начальник" };
        bool inProgram = true;

        while (inProgram)
        {
            Console.Clear();
            Console.Write($"Меню:" +
                $"\n{CommandAddDossier} - Добавить досье." +
                $"\n{CommandShowAllDossier} - Показать все досье." +
                $"\n{CommandRemoveDossier} - Удалить досье." +
                $"\n{CommandSearchByLastName} - Поиск по фамилии." +
                $"\n{CommandExit} - Завершить прогрумму." +
                $"\nВвод: ");
            string userInput = Console.ReadLine();

            switch (userInput)
            {
                case CommandAddDossier:
                    AddDossier(ref employeeFullNames, ref employeePositions);
                    break;

                case CommandShowAllDossier:
                    ShowAllDossier(employeeFullNames, employeePositions);
                    break;

                case CommandRemoveDossier:
                    RemoveDossier(ref employeeFullNames, ref employeePositions);
                    break;

                case CommandSearchByLastName:
                    SearchByLastName(employeeFullNames, employeePositions);
                    break;

                case CommandExit:
                    inProgram = false;
                    break;

                default:
                    Console.Clear();
                    Console.WriteLine("Ошибка ввода.");
                    Console.ReadKey();
                    break;
            }
        }

        Console.WriteLine("Программа завершена.");
        Console.ReadKey();
    }

    static void AddDossier(ref string[] employeeFullNames, ref string[] employeePositions)
    {
        Console.Clear();
        Console.Write("Введи ФИО: ");
        employeeFullNames = AddUserInputToArray(employeeFullNames);

        Console.Write("Введи должность: ");
        employeePositions = AddUserInputToArray(employeePositions);

        Console.WriteLine("Сотрюдник добавлен.");
        Console.ReadKey();
    }

    static string[] AddUserInputToArray( string[] array)
    {
        string[] tempArray = new string[array.Length + 1];
        string userInput = Console.ReadLine();

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

        tempArray[array.Length] = userInput;

        return tempArray;
    }

    static void ShowAllDossier(string[] employeeFullNames, string[] employeePositions)
    {
        Console.Clear();

        for (int i = 0; i < employeeFullNames.Length; i++)
        {
            Console.WriteLine($"{i + 1}. {employeeFullNames[i]} - {employeePositions[i]}");
        }

        Console.ReadKey();
    }

    static void RemoveDossier(ref string[] employeeFullNames, ref string[] employeePositions)
    {
        Console.Clear();

        Console.WriteLine("Введите номер сотрудника для его удаление из учета:");

        int number = ReadNumber();
        int employeeIndex = number - 1;

        if (number > employeeFullNames.Length || number <= 0)
        {
            Console.WriteLine("Нету сотрудника под данным номером");
        }
        else
        {
            employeeFullNames = DeleteElement(employeeFullNames, employeeIndex);
            employeePositions = DeleteElement(employeePositions, employeeIndex);

            Console.WriteLine("Сотрудник был удален из учета");
        }

        Console.ReadKey();
    }

    static string[] DeleteElement(string[] dossierNames, int dossierNumber)
    {
        string[] temp = new string[dossierNames.Length - 1];

        for (int i = 0; i < dossierNumber; i++)
        {
            temp[i] = dossierNames[i];
        }

        for (int i = dossierNumber; i < temp.Length; i++)
        {
            temp[i] = dossierNames[i + 1];
        }

        return temp;
    }

    static void SearchByLastName(string[] employeeFullNames, string[] employeePositions)
    {
        Console.Clear();

        Console.WriteLine("Введите фамилию сотрудника для его поиска:");

        string lastName = Console.ReadLine();

        bool isFound = false;

        for (int i = 0; i < employeeFullNames.Length; i++)
        {
            string[] splitPartOfName = employeeFullNames[i].Split(' ');

            if (string.Equals(splitPartOfName[0], lastName, StringComparison.CurrentCultureIgnoreCase))
            {
                Console.WriteLine($"{i + 1}. {employeeFullNames[i]} - {employeePositions[i]}");
                isFound = true;
            }
        }

        if (isFound == false)
        {
            Console.WriteLine("Сотрудник не найден");
        }

        Console.ReadKey();
    }

    static int ReadNumber()
    {
        int number;

        while (int.TryParse(Console.ReadLine(), out number) == false)
        {
            Console.Write("Ошибка ввода.");
        }

        return number;
    }
}