C# I attached a solution to Exercise 15-1. So please use it to do this exercise below. I also attached figure 15-11 that is mentioned in this exercise.

In this exercise, you'll modify your solution to exercise 15-1 so the clones are stored in a CustomerList object that implements an enumerator. 1. Implement the IEnumerable interface for the CustomerList class. (This class wasn't used by the previous exercise.) To do that, implement the GetEnumerator method as described in Figure 15-11. 2. Modify the code in the form class so it stores the cloned Customer object in a CustomerList object rather than in a List object

3. Run the application and test it to be sure it works properly C# Exercise 15-2 is the exercise I need and it need Exercise 15-1 to do. However, I attached a solution to Exercise 15-1. So please use it to do Exersise 15-2. I also attached figure 15-11 that is mentioned in Exercise 15-2.

using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Windows.Forms; using CloneCustomer.DataValidation;

namespace CloneCustomer { public partial class Form1 : Form { public Form1() { InitializeComponent(); }

private Customer customer; private List customers;

private void Form1_Load(object sender, System.EventArgs e) { customer = new Customer("John", "Mendez", "jmendez@msysco.com"); lblCustomer.Text = customer.GetDisplayText(); }

private void btnClone_Click(object sender, System.EventArgs e) { if (IsValidData()) { int count = Convert.ToInt16(txtCopies.Text); customers = MakeCustomerList(customer, count); lstCustomers.Items.Clear(); foreach (Customer c in customers) { lstCustomers.Items.Add(c.GetDisplayText()); } } }

private bool IsValidData() { return Validator.IsPresent(txtCopies) && Validator.IsInt32(txtCopies); }

private List MakeCustomerList(Customer c, int count) { List customerList = new List(); for (int i = 0; i

private void btnExit_Click(object sender, System.EventArgs e) { this.Close(); }

} } ___________________________________________________________________

using System;

namespace CloneCustomer { public class Customer : ICloneable { private string firstName; private string lastName; private string email;

public Customer() { }

public Customer(string firstName, string lastName, string email) { this.FirstName = firstName; this.LastName = lastName; this.Email = email; }

///

/// The Customer First Name. ///

public string FirstName { get { return firstName; } set { firstName = value; } }

public string LastName { get { return lastName; } set { lastName = value; } }

public string Email { get { return email; } set { email = value; } }

public string GetDisplayText() => firstName + " " + lastName + ", " + email;

public object Clone() => new Customer(this.FirstName, this.LastName, this.Email); } } _____________________________________________________

namespace CloneCustomer { internal interface ICloneCustomers { } }

_____________________________________________________

using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Windows.Forms;

namespace CloneCustomer.DataValidation { ///

/// Validator Utility Class to Validate inputs ///

public static class Validator { private static string title = "Entry Error";

///

/// Title Propertu of Validator Class Object ///

public static string Title { get { return title; } set { title = value; } }

///

/// Check if Input is Present ///

///TextBox Type /// bool public static bool IsPresent(TextBox textBox) { if (textBox.Text == "") { MessageBox.Show(textBox.Tag + " is a required field.", Title); textBox.Focus(); return false; } return true; }

public static bool IsDecimal(TextBox textBox) { decimal number = 0m; if (Decimal.TryParse(textBox.Text, out number)) { return true; } else { MessageBox.Show(textBox.Tag + " must be a decimal value.", Title); textBox.Focus(); return false; } }

public static bool IsInt32(TextBox textBox) { int number = 0; if (Int32.TryParse(textBox.Text, out number)) { return true; } else { MessageBox.Show(textBox.Tag + " must be an integer.", Title); textBox.Focus(); return false; } }

public static bool IsWithinRange(TextBox textBox, decimal min, decimal max) { decimal number = Convert.ToDecimal(textBox.Text); if (number max) { MessageBox.Show(textBox.Tag + " must be between " + min + " and " + max + ".", Title); textBox.Focus(); return false; } return true; }

public static bool IsValidEmail(TextBox textBox) { if (textBox.Text.IndexOf("@") == -1 || textBox.Text.IndexOf(".") == -1) { MessageBox.Show(textBox.Tag + " must be a valid email address.", Title); textBox.Focus(); return false; } else { return true; } } } } ____________________________________________

using System; using System.Collections.Generic;

namespace CloneCustomer { public class CustomerList { private List customers = new List();

public int Count => customers.Count;

public Customer this[int i] => customers[i];

public void Add(Customer customer) => customers.Add(customer); } }