C#

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Xml;

namespace Inlämning_1PersonInfo
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private List<Person> people = new List<Person>();
        private List<Person> searchPeople = new List<Person>();

        private void Form1_Load(object sender, EventArgs e)
        {
            string path = Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData);
            if (!Directory.Exists(path + "\\Address Book - Patte"))
            {
                Directory.CreateDirectory(path + "\\Address Book - Patte");
            }
            if (!File.Exists(path + "\\Address Book - Patte\\settings.xml"))
            {
                XmlTextWriter xW = new XmlTextWriter(path + "\\Address Book - Patte\\settings.xml", Encoding.UTF8);
                xW.WriteStartElement("People");
                xW.WriteEndElement();
                xW.Close();
            }
            XmlDocument xDoc = new XmlDocument();
            xDoc.Load(path + "\\Address Book - Patte\\settings.xml");
            foreach (XmlNode xNode in xDoc.SelectNodes("People/Person"))
            {
                Person P = new Person();
                P.name = xNode.SelectSingleNode("Name").InnerText;
                P.streetAddress = xNode.SelectSingleNode("Streetaddress").InnerText;
                P.zipCode = xNode.SelectSingleNode("Zipcode").InnerText;
                P.city = xNode.SelectSingleNode("City").InnerText;
                P.phoneNumber = xNode.SelectSingleNode("Phonenumber").InnerText;
                P.mail = xNode.SelectSingleNode("Mail").InnerText;
                people.Add(P);
                listPeople.Items.Add(P.name + "                                                                                                                                                                 " + P.streetAddress + " " + P.zipCode + " " + P.city + " " + P.phoneNumber + " " + P.mail);
            }
        }

        private class Person
        {
            public string name
            {
                get;
                set;
            }

            public string streetAddress
            {
                get;
                set;
            }

            public string zipCode
            {
                get;
                set;
            }

            public string city
            {
                get;
                set;
            }

            public string phoneNumber
            {
                get;
                set;
            }

            public string mail
            {
                get;
                set;
            }
        }

        private void cmdAddContact_Click(object sender, EventArgs e)
        {
            Person p = new Person();
            p.name = txtName.Text;
            p.streetAddress = txtStreetAddress.Text;
            p.zipCode = txtZipCode.Text;
            p.city = txtCity.Text;
            p.phoneNumber = txtPhoneNumber.Text;
            p.mail = txtMail.Text;

            txtName.Text = "";
            txtStreetAddress.Text = "";
            txtZipCode.Text = "";
            txtCity.Text = "";
            txtPhoneNumber.Text = "";
            txtMail.Text = "";
            people.Add(p);
            listPeople.Items.Add(p.name + "                                                                                                                                                                           " + p.streetAddress + " " + p.zipCode + " " + p.city + " " + p.phoneNumber + " " + p.mail);
        }

        private void listPeople_SelectedIndexChanged(object sender, EventArgs e)
        {
            if (listPeople.SelectedItems.Count > 0)
            {
                try
                {
                    txtName.Text = people[listPeople.SelectedItems[0].Index].name;
                    txtStreetAddress.Text = people[listPeople.SelectedItems[0].Index].streetAddress;
                    txtZipCode.Text = people[listPeople.SelectedItems[0].Index].zipCode;
                    txtCity.Text = people[listPeople.SelectedItems[0].Index].city;
                    txtPhoneNumber.Text = people[listPeople.SelectedItems[0].Index].phoneNumber;
                    txtMail.Text = people[listPeople.SelectedItems[0].Index].mail;
                }
                catch { }
            }
        }

        private void cmdRemove_Click(object sender, EventArgs e)
        {
            remove();

            txtName.Text = "";
            txtStreetAddress.Text = "";
            txtZipCode.Text = "";
            txtCity.Text = "";
            txtPhoneNumber.Text = "";
            txtMail.Text = "";
        }

        private void remove()
        {
            try
            {
                people.RemoveAt(listPeople.SelectedItems[0].Index);
                listPeople.Items.Remove(listPeople.SelectedItems[0]);
            }
            catch { }
        }

        private void removeToolStripMenuItem_Click(object sender, EventArgs e)
        {
            remove();
        }

        private void cmdSaveChanges_Click(object sender, EventArgs e)
        {
            try
            {
                people[listPeople.SelectedItems[0].Index].name = txtName.Text;
                people[listPeople.SelectedItems[0].Index].streetAddress = txtStreetAddress.Text;
                people[listPeople.SelectedItems[0].Index].zipCode = txtZipCode.Text;
                people[listPeople.SelectedItems[0].Index].city = txtCity.Text;
                people[listPeople.SelectedItems[0].Index].phoneNumber = txtPhoneNumber.Text;
                people[listPeople.SelectedItems[0].Index].mail = txtMail.Text;
                listPeople.SelectedItems[0].Text = txtName.Text;
            }
            catch { }
        }

        private void Form1_FormClosing(object sender, FormClosingEventArgs e)
        {
            XmlDataDocument xDoc = new XmlDataDocument();
            string path = Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData);
            xDoc.Load(path + "\\Address Book - Patte\\settings.xml");
            XmlNode xNode = xDoc.SelectSingleNode("People");
            xNode.RemoveAll();
            foreach (Person p in people)
            {
                XmlNode xTop = xDoc.CreateElement("Person");
                XmlNode xName = xDoc.CreateElement("Name");
                XmlNode xStreetAddress = xDoc.CreateElement("Streetaddress");
                XmlNode xZipCode = xDoc.CreateElement("Zipcode");
                XmlNode xCity = xDoc.CreateElement("City");
                XmlNode xPhoneNumber = xDoc.CreateElement("Phonenumber");
                XmlNode xMail = xDoc.CreateElement("Mail");
                xName.InnerText = p.name;
                xStreetAddress.InnerText = p.streetAddress;
                xZipCode.InnerText = p.zipCode;
                xCity.InnerText = p.city;
                xPhoneNumber.InnerText = p.phoneNumber;
                xMail.InnerText = p.mail;
                xTop.AppendChild(xName);
                xTop.AppendChild(xStreetAddress);
                xTop.AppendChild(xZipCode);
                xTop.AppendChild(xCity);
                xTop.AppendChild(xPhoneNumber);
                xTop.AppendChild(xMail);
                xDoc.DocumentElement.AppendChild(xTop);
            }
            xDoc.Save(path + "\\Address Book - Patte\\settings.xml");
        }

        public void cmdSearch_Click(object sender, EventArgs e)
        {
            if (txtSearch.Text != "")
            {
                for (int i = listPeople.Items.Count - 1; i >= 0; i--)
                {
                    var item = listPeople.Items[i];
                    if (item.Text.ToLower().Contains(txtSearch.Text.ToLower()))
                    {
                    }
                    else
                    {
                        listPeople.Items.Remove(item);
                    }
                }
                if (listPeople.SelectedItems.Count > 0)
                {
                    listPeople.Focus();
                    people.RemoveAt(listPeople.SelectedItems[0].Index);
                    listPeople.Items.Remove(listPeople.SelectedItems[0]);
                }
            }
            else { }
            //    LoadContacts();
            //RefreshAll();
        }

        private void cmdSearchperson_Click(object sender, EventArgs e)
        {
        }

        private void cmdClear_Click(object sender, EventArgs e)
        {
            Application.Restart();
        }
    }
}