Billing Management System C#- in Windows Forms Application c#

Billing Management System C#- in  Windows Forms Application c#:

Stock And Billing Management System project is a desktop application which is implemented in C# .net platform. 

C#(code)............

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Windows.Forms;

namespace biling_system

{

    public partial class Form1 : Form

    {

        static int i = 0, total = 0;

        public Form1()

        {

            InitializeComponent();

        }

        private void Form1_Load(object sender, EventArgs e)

        {

        }

        private void button1_Click(object sender, EventArgs e)

        {

            int price, quantity;

            string item;

            price = int.Parse(listView1.SelectedItems[0].SubItems[1].Text);

            quantity = int.Parse(textBox1.Text);

            price = price * quantity;

            item = listView1.SelectedItems[0].Text;

            listView2.Items.Add(item);

            listView2.Items[i].SubItems.Add(price.ToString());

            i++;

            total = total + price;

            lbl_total.Text = total.ToString();

            lbl_total.Visible = true;          

        }

        private void button2_Click(object sender, EventArgs e)

        {

            if (listView2.SelectedItems != null)

            {

                int deduct = 0;

                var confirm = MessageBox.Show("Are Sure You Want Cancle Order", "DELETE ORDER", MessageBoxButtons.YesNo, MessageBoxIcon.Warning);

                if (confirm == DialogResult.Yes)

                {

                    for (int i = 0; i < listView2.Items.Count; i++)

                    {

                        if (listView2.Items[i].Selected)

                        {

                            deduct = int.Parse(listView2.Items[i].SubItems[1].Text);

                            listView2.Items[i].Remove();

                            i--;

                        }

                    }

                }

                total = total - deduct;

                lbl_total.Text = total.ToString();

                lbl_total.Visible = true;

            }

            else

            {

                MessageBox.Show("Select Item For Cancle order", "Cancle Order", MessageBoxButtons.OK, MessageBoxIcon.Error);

            }

        }

    }

}