Paste 1

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;

namespace RememberMyPasswords
{
    public partial class Form1 : Form
    {
        string removewhat;
        List<string> names = new List<string>();
        List<string> passwords = new List<string>();
        List<string> emails = new List<string>();
        List<string> websites = new List<string>();

        public Form1()
        {
            InitializeComponent();
        }

        //Load
        private void Form1_Load
        (object sender, EventArgs e)
        {
        }

        private void checkBox1_CheckedChanged(object sender, EventArgs e)
        {
            if(checkBox1.Checked)
            {
                treeView1.Sort();
            }
            else if(checkBox1.Checked == false)
            {

            }
        }

        public void add()
        {

            TreeView t = new TreeView();
            t = treeView1;
            names.Add(textBox1.Text);
            passwords.Add(textBox2.Text);
            emails.Add(textBox3.Text);
            websites.Add(textBox4.Text);

            string addedname = textBox1.Text;
            string addedpass = textBox2.Text;
            string addedemail = textBox3.Text;
            string addedwebsite = textBox4.Text;
            string nodename = textBox5.Text;
            int treecount = 0;

            removewhat = nodename;

            t.Nodes.Add(nodename);
            t.Nodes[treecount].Nodes.Add($"Username: {addedname?? "Empty"}");
            t.Nodes[treecount].Nodes.Add($"Password: {addedpass?? "Empty"}");
            t.Nodes[treecount].Nodes.Add($"Email: {addedemail?? "Empty"}");
            t.Nodes[treecount].Nodes.Add($"Website: {addedwebsite ?? "Empty"}");

            treecount += 1;

            removewhat = null;
            nodename = null;
            addedname = null;
            addedpass = null;
            addedemail = null;
            addedwebsite = null;

            textBox3.Clear();
            textBox4.Clear();
            textBox1.Clear();
            textBox2.Clear();
            textBox5.Clear();
        }

        private void button1_Click_1(object sender, EventArgs e)
        {
            add();
        }

        private void treeView1_AfterSelect_1
        (object sender, TreeViewEventArgs e)
        {
            var requestresponse = MessageBox.Show($"Are you sure you want to remove \"{treeView1.SelectedNode}\"", "", MessageBoxButtons.YesNo);
            if (requestresponse.ToString() == "Yes")
            {
                treeView1.Nodes.Remove(treeView1.SelectedNode);
            }
            else { };
        }
    }
}