using System;

using System.Collections.Generic;

using System.Linq;

using System.Globalization;

​

public class Program

{

    const int MAX_PEOPLE = 10;

    enum MenuOptions

    {

        AddPerson = 1,

        EditPerson,

        DeletePerson,

        SearchPeople,

        DisplayPeople,

        Quit

    }

​

    struct Person

    {

        public string Name;

        public string PhoneNumber;

    }

​

    public static void Main(string[] args)

    {

        Person[] people = new Person[MAX_PEOPLE];

        bool running = true;

        int userChoice;

        int currentPersonIndex = 0;

        while (running)

        {

            DisplayMenu(people, currentPersonIndex);

            int.TryParse(Console.ReadLine(), out userChoice);

            switch ((MenuOptions)userChoice)

            {

                case MenuOptions.AddPerson:

                    AddPerson(people, currentPersonIndex);

                    currentPersonIndex++;

                    break;

                case MenuOptions.EditPerson:

                    EditPerson(people, currentPersonIndex);

                    break;

                case MenuOptions.DeletePerson:

                    people = DeletePerson(people, currentPersonIndex);

                    currentPersonIndex--;

                    break;

                case MenuOptions.DisplayPeople:

                    if (currentPersonIndex > 0)

                    {

                        DisplayPeople(people);

                    }

​

                    break;

                case MenuOptions.SearchPeople:

                    if (currentPersonIndex > 0)

                    {

                        SearchPeople(people, currentPersonIndex);

                    }

​

                    break;

                case MenuOptions.Quit:

                    running = false;

                    break;

            }

        }

    }

​

    static void DisplayMenu(Person[] people, int currentIndex)

    {

        Console.WriteLine("\nPlease choose an option...");

        if (currentIndex < MAX_PEOPLE)

        {

            Console.WriteLine("{0}: Add a new person.", (int)MenuOptions.AddPerson);

        }

​

        if (currentIndex > 0)

        {

            Console.WriteLine("{0}: Edit a  person.", (int)MenuOptions.EditPerson);

            Console.WriteLine("{0}: Delete a person.", (int)MenuOptions.DeletePerson);

            Console.WriteLine("{0}: Search a person.", (int)MenuOptions.SearchPeople);

            Console.WriteLine("{0}: Display the list of people.", (int)MenuOptions.DisplayPeople);

        }

​

        Console.WriteLine("{0}: Quit.", (int)MenuOptions.Quit);

        Console.WriteLine();

    }

​

    static Person GetPersonFromUser()

    {

        Person person;

        Console.WriteLine("\nEnter details for the new person...");

        Console.Write("Name: ");

        person.Name = Console.ReadLine();

        Console.Write("Phone Number: ");

        person.PhoneNumber = Console.ReadLine();

        return person;

    }

​

    static int GetRecordNo(Person[] people)

    {

        int recordno = 0;

        DisplayPeople(people);

        Console.WriteLine("\nEnter Record No of the person...");

        Console.Write("Record No: ");

        int.TryParse(Console.ReadLine(), out recordno);

        return recordno;

    }

​

    static void AddPerson(Person[] people, int currentIndex)

    {

        if (currentIndex < MAX_PEOPLE)

        {

            people[currentIndex] = GetPersonFromUser();

        }

    }

​

    static void EditPerson(Person[] people, int currentIndex)

    {

        int recordno = GetRecordNo(people);

        Person person = new Person();

        if (recordno != 0 && recordno <= MAX_PEOPLE)

        {

            Console.WriteLine("\nEnter new information of the person to edit...");

            Console.Write("New Name: ");

            person.Name = Console.ReadLine();

            Console.Write("New Phone Number: ");

            person.PhoneNumber = Console.ReadLine();

            people[recordno - 1] = person;

            Console.WriteLine("\n Record is updated...");

        }

    }

​

    static Person[] DeletePerson(Person[] people, int currentIndex)

    {

        int recordno = GetRecordNo(people);

        if (recordno != 0 && recordno <= MAX_PEOPLE)

        {

            var lst = new List<Person>(people);

            lst.RemoveAt(recordno - 1);

            people = lst.ToArray();

            Console.WriteLine("\n Record is deleted...");

        }

​

        return people;

    }

​

    static void SearchPeople(Person[] people, int currentIndex)

    {

        string searchterm = String.Empty;

        Console.WriteLine("\nEnter name of the person to search...");

        Console.Write("Name: ");

        searchterm = Console.ReadLine();

        List<Person> searchresult = new List<Person>();

        for (int k = 0; k < currentIndex; k++)

        {

            if (people[k].Name.IndexOf(searchterm) > -1)

                searchresult.Add(people[k]);

        }

​

        var selectedpeople = searchresult.ToArray();

        if (selectedpeople.Length == 0)

            Console.WriteLine("\nNo record is found...");

        else

            DisplayPeople(selectedpeople);

    }

​

    static void DisplayPeople(Person[] people)

    {

        Console.WriteLine();

        Console.WriteLine("".PadLeft(50, '*'));

        Console.WriteLine("{0} {1} {2}", "No".PadRight(4), "| Name".PadRight(20), "| Phone Number".PadRight(10));

        Console.WriteLine("".PadLeft(50, '-'));

        int i = 0;

        foreach (Person person in people)

        {

            i++;

            if (person.Name != null)

            {

                Console.WriteLine("{0} | {1} | {2}", i.ToString().PadRight(4), person.Name.PadRight(18), person.PhoneNumber);

            }

        }

​

        Console.WriteLine("".PadLeft(50, '*'));

        Console.WriteLine();

    }

}