gistfile1.txt

using System;

namespace _My_New_Home_Work_
{
    internal class Program
    {

        static void Main(string[] args)
        {
            bool isWork = true;
            
            const string CommandAddDossier = "1";
            const string CommandOutputDossier = "2";
            const string CommandDeleteDossiers = "3";
            const string CommandLastNameSearch = "4";
            const string CommandExit = "5";

            string[] workers = new string[0];
            string[] posts = new string[0];

            while (isWork)
            {
                Console.WriteLine("1-Добавьте досье\n2-Вывести все досье\n3-Удалить досье\n4-Поиск по фамилии\n5-Выход");

                string userInput = Console.ReadLine();

                switch (userInput)
                {
                    case CommandAddDossier:
                        AddDossier(ref workers,ref posts);
                        break;

                    case CommandOutputDossier:
                        ShowDossiers(workers,posts);
                        break;

                    case CommandDeleteDossiers:
                        ShowDossiers(workers, posts);
                        DeleteDossier(ref workers, ref posts);
                        break;

                    case CommandLastNameSearch:
                        FindLastName(workers, posts);
                        break;

                    case CommandExit:
                        isWork = false;
                        break;
                }

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

        static void AddDossier(ref string[] workers, ref string[] posts)
        {
            Console.WriteLine("Введите ФИО работника: ");
            string userInput1 = Console.ReadLine();

            Console.WriteLine("Введите должность: ");
            string userInput2 = Console.ReadLine();

            ExpandArray(ref workers, userInput1);
            ExpandArray(ref posts, userInput2);

            Console.WriteLine($"{workers[workers.Length - 1]} {posts[posts.Length - 1]}");
        }
        
        static void ShowDossiers(string[] workers,string[] posts)
        {
           for (int i = 0; i < workers.Length; i++)
           {
               Console.WriteLine($"{i +  1}) {workers[i]} {posts[i]}");
           }
        }

        static void DeleteDossier(ref string[] workers, ref string[] posts)
        {
            Console.WriteLine("\nВведите порядковый номер для удаления: ");

            int userNumber = int.Parse(Console.ReadLine()) - 1;

            workers = DeleteElementArray(workers, userNumber);
            posts = DeleteElementArray(posts, userNumber);
        }

        static void FindLastName(string[] workers, string[] posts)
        {
            Console.Write("Введите фамилию: ");
            
            string userInput = Console.ReadLine();         

            for (int i = 0; i < workers.Length; i++)
            {
                string[] splitText = workers[i].Split();

                if (userInput == splitText[0])
                {
                    Console.WriteLine($"{workers[i]} {posts[i]}");
                }
            }
        }

        static void ExpandArray(ref string[] array,string userInput)
        {
            string[] tempArray = new string[array.Length + 1];

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

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

        static string[] DeleteElementArray(string[] workers,int userNumber)
        {
            string[] tempArray = new string[workers.Length - 1];

            for (int i = 0; i < userNumber; i++)
                tempArray[i] = workers[i];

            for (int i = userNumber + 1; i < workers.Length; i++)
                tempArray[i - 1] = workers[i];

            return tempArray;
        }
    }
}