frmSettle.cs

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 System.Data.SqlClient;

namespace pos_and_inventory_csharp
{
    public partial class frmSettle : Form
    {
        frmPOS fpos;
        SqlConnection cn = new SqlConnection();
        SqlCommand cm = new SqlCommand();
        DBConnection dbcon = new DBConnection();
        SqlDataReader dr;

        public frmSettle(frmPOS fp)
        {
            InitializeComponent();
            cn = new SqlConnection(dbcon.MyConnection());
            fpos = fp;
        }

        private void pictureBox1_Click(object sender, EventArgs e)
        {
            this.Dispose();
        }

        private void txtCash_TextChanged(object sender, EventArgs e)
        {
            try
            {
                double sale = double.Parse(txtSale.Text);
                double cash = double.Parse(txtCash.Text);
                double change = cash - sale;
                txtChange.Text = change.ToString("#,##0.00");

            }catch(Exception ex)
            {
                txtChange.Text = "0.00";
            }
        }

        private void btn7_Click(object sender, EventArgs e)
        {
            txtCash.Text += btn7.Text;
        }

        private void btn8_Click(object sender, EventArgs e)
        {
            txtCash.Text += btn8.Text;
        }

        private void btn9_Click(object sender, EventArgs e)
        {
            txtCash.Text += btn9.Text;
        }

        private void btnc_Click(object sender, EventArgs e)
        {
            txtCash.Clear();
            txtCash.Focus();
        }

        private void btn4_Click(object sender, EventArgs e)
        {
            txtCash.Text += btn4.Text;
        }

        private void btn5_Click(object sender, EventArgs e)
        {
            txtCash.Text += btn5.Text;
        }

        private void btn6_Click(object sender, EventArgs e)
        {
            txtCash.Text += btn6.Text;
        }

        private void btn0_Click(object sender, EventArgs e)
        {
            txtCash.Text += btn0.Text;
        }

        private void btn1_Click(object sender, EventArgs e)
        {
            txtCash.Text += btn1.Text;
        }

        private void btn2_Click(object sender, EventArgs e)
        {
            txtCash.Text += btn2.Text;
        }

        private void btn3_Click(object sender, EventArgs e)
        {
            txtCash.Text += btn3.Text;
        }

        private void btn00_Click(object sender, EventArgs e)
        {
            txtCash.Text += btn00.Text;
        }

        private void btnEnter_Click(object sender, EventArgs e)
        {
            try
            {
                if((double.Parse(txtChange.Text) < 0) || (txtCash.Text == String.Empty) )
                {
                    MessageBox.Show("Insufficient Amount. Please enter the correcet!", "Warning", MessageBoxButtons.OK, MessageBoxIcon.Warning);
                    return;
                }
                else
                {
                    for (int i = 0; i < fpos.dataGridView1.Rows.Count; i++)
                    {
                        cn.Open();
                        cm = new SqlCommand("update tblproduct set qty = qty - " + int.Parse(fpos.dataGridView1.Rows[i].Cells[5].Value.ToString())+ " where pcode = '"+ fpos.dataGridView1.Rows[i].Cells[2].Value.ToString() + "'", cn);
                        cm.ExecuteNonQuery();
                        cn.Close();

                        cn.Open();
                        cm = new SqlCommand("USE [POS_DEMO_DB] update tblcart set status = 'Sold' where id like'" + fpos.dataGridView1.Rows[i].Cells[1].Value.ToString() +"'", cn);
                        cm.ExecuteNonQuery();
                        cn.Close();
                    }
                    frmReceipt frm = new frmReceipt(fpos);
                    frm.LoadReport(txtCash.Text, txtChange.Text);
                    frm.ShowDialog();

                    MessageBox.Show("Payment Successfully Saved!", "Payment", MessageBoxButtons.OK, MessageBoxIcon.Information);


                    //fpos.LoadCart();

                    this.Dispose();
                    fpos.dataGridView1.Rows.Clear();
                    fpos.Refresh();
                    fpos.dataGridView1.Rows.Clear();
                    fpos.GetTransNo();
                    fpos.LoadCart();

                }

            }catch (Exception ex)
            {
                cn.Close();
                MessageBox.Show(ex.Message,"Error Enter Click");
            }
        }
    }
}