C # Simple store cash register system v1.0 (2-1)

C # Simple store cash register system v1.0 (2-1)

1. Original:

   • Applications for benefits and a simple factory pattern programming objects (inheritance, polymorphism)

2. just now:

   • Make a simple cash register application form

Before you can reference calculator essays

Create a form program

Client code

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 商城收银软件
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        double total = 0.0d;//Declare a double variable, with a total calculated total 
        Private  void the button1_Click ( Object SENDER, EventArgs E) 
        { 
            double totalPrices = Convert.ToDouble (txtPrice.Text) * Convert.ToDouble (txtNum.Text); 
total = total + totalPrices; // each product sum calculated 
lbxList.Text = " Price: " + + txtPrice.Text " number: " + txtNum.Text + " total: " + totalPrices.ToString ();   // display information 
            lblResult.Text = total. the ToString (); // display the total count 
         } 
     } 
}

Achieve results

Now add a discount function

 

Client code

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 商城收银软件
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        double total = 0.0d;//Declare a double variable, with a total calculated total 
        Private  void the button1_Click ( Object SENDER, EventArgs E) 
        { 
            double totalPrices = 0D;
             Switch (cbxType.SelectedIndex) 
            { 
                Case  0 : 
                    totalPrices = Convert.ToDouble (txtPrice.Text) * Convert.ToDouble (txtNum.Text);
                     BREAK ;
                 Case  . 1 : 
                    totalPrices = Convert.ToDouble (txtPrice.Text) * Convert.ToDouble (txtNum.Text) * 0.8 ;
                     BREAK ;
                case 2:
                    totalPrices = Convert.ToDouble(txtPrice.Text) * Convert.ToDouble(txtNum.Text)*0.7;
                    break;
                case 3:
                    totalPrices = Convert.ToDouble(txtPrice.Text) * Convert.ToDouble(txtNum.Text)*0.5;
                    break;
            }
            total = total + totalPrices;
            lbxList.Text = "单价:" + txtPrice.Text + "数量:" + txtNum.Text + " " + CbxType.SelectedItem + " Total: " + totalPrices.ToString ();   
            lblResult.Text = total.ToString (); 


        } 
        Private  void the Form1_Load ( Object SENDER, EventArgs E) 
        { 
            cbxType.Items.AddRange ( new new  Object [] { " normal charge " , " discount of twenty " , " play Qizhe " , " half off " }); 
            cbxType.SelectedIndex = 0 ; 
        }
}

 

 

to sum up

Like Convert.ToDouble () many of these duplicate

Discount branch can be considered reconstructed

The client is instantiated only need to change out of operation

You can try using a simple factory implementation

Under an essay on the use of simple factory store cash register system to achieve v1.0