using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using System.Windows;

using System.Windows.Controls;

using System.Windows.Data;

using System.Windows.Documents;

using System.Windows.Input;

using System.Windows.Media;

using System.Windows.Media.Imaging;

using System.Windows.Navigation;

using System.Windows.Shapes;

​

namespace Mod_9_Homework

{

    /// <summary>

    /// Interaction logic for MainWindow.xaml

    /// </summary>

    public partial class MainWindow : Window

    {

        // Create a collection to store Student objects

        private List<Student> listStudents = new List<Student>();

        private static int index = -1;

​

        public MainWindow()

        {

            InitializeComponent();

        }

​

        private void btnCreateStudent_Click(object sender, RoutedEventArgs e)

        {

            // Create a student object and add it to the collection

            Student student = new Student(txtFirstName.Text, txtLastName.Text, txtCity.Text);

            listStudents.Add(student);

​

            // Clear the contents of the text boxes

            txtFirstName.Clear();

            txtLastName.Clear();

            txtCity.Clear();

​

        }

​

        private void btnPrevious_Click(object sender, RoutedEventArgs e)

        {

            if (listStudents.Count != 0)

            {

                if (index == -1) index = listStudents.Count - 1;

                else index = (index + listStudents.Count - 1) % listStudents.Count;

                txtFirstName.Text = listStudents[index].FirstName;

                txtLastName.Text = listStudents[index].LastName;

                txtCity.Text = listStudents[index].City;

            }

        }

​

        private void btnNext_Click(object sender, RoutedEventArgs e)

        {

            if (listStudents.Count != 0)

            {

                if (index == -1) index = 0;

                else index = (index + 1) % listStudents.Count;

                txtFirstName.Text = listStudents[index].FirstName;

                txtLastName.Text = listStudents[index].LastName;

                txtCity.Text = listStudents[index].City;

            }

        }

​

    }

}

​

​

namespace Mod_9_Homework

{

    public class Student

    {

        private string firstName;

        private string lastName;

        private string city;

        public string FirstName

        {

            get { return firstName; }

            set { firstName = value; }

        }

        public string LastName

        {

            get { return lastName; }

            set { lastName = value; }

        }

​

        public string City

        {

            get { return city; }

            set { city = value; }

        }

​

        public Student()

        { 

        }

​

        public Student(string firstName, string lastName, string city)

        {

            this.FirstName = firstName;

            this.LastName = lastName;

            this.City = city;

        }

​

    }

}

​

​