这个是C#大作业，写作业很用心，写了很久，所以留存一下。不是现在的是之前的的期末作业，现在才想着整理一下

实现功能：

1、商家登录；客户的登录、注册。
2、商家界面实现了对菜单的增、删、改、查；还有订单的查看、查询、结账（删除订单）、查看已结账订单、关闭；退出系统。
3、用户界面实现了菜单的查看，查询，新建订单，选择餐桌，保存订单，增加菜品，退出。

C#语言实现在线点餐系统，具体功能如下图

登录界面

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace MenuSystemWss
{

 public partial class Form1 : Form
 {

 int dlsf=0;
 /* SqlConnection sqlcon;
 SqlCommand sqlcom;
 SqlDataReader sqlsdr;*/


 BaseInfo baseinfo = new BaseInfo();//
 BaseInfo.GkInfo gkinfo = new BaseInfo.GkInfo();//
 public Form1()
 {
 InitializeComponent();

 }
 public void dengluzt()
 {
 DataSet ds = null;
 gkinfo.Gk_num = textBox1.Text.Trim();
 ds = baseinfo.DengLu(gkinfo, "db_menu");
 gkinfo.Gk_zt = 1;
 gkinfo.Gk_apw = gkinfo.Gk_pw;
 gkinfo.Gk_name = ds.Tables[0].Rows[0][1].ToString().Trim();
 baseinfo.Updatgk(this.gkinfo);
 }
 private void button1_Click(object sender, EventArgs e)
 {
 if (radioButton1.Checked) dlsf = 1;
 if (radioButton2.Checked) dlsf = 2;
 if (textBox1.Text.Trim() == "")
 {
 label3.Text = "账号不能为空";
 textBox1.Focus();
 return;
 }
 else
 if (textBox2.Text.Trim() == "")
 {
 label3.Text = "密码不能为空";
 textBox1.Focus();
 return;
 }
 else
 if (dlsf == 2)
 {
 
 try
 {
 DataSet ds = null;
 gkinfo.Gk_num = textBox1.Text.Trim();
 gkinfo.Gk_pw = textBox2.Text.Trim();
 ds = baseinfo.DengLu(gkinfo, "db_menu");
 if (ds== null||ds.Tables.Count == 0||(ds.Tables.Count == 1 && ds.Tables[0].Rows.Count == 0))
 {
 MessageBox.Show("用户名错误！");
 return;
 }
 else
 if (ds.Tables[0].Rows[0][2].ToString().Trim() != textBox2.Text.Trim())
 { MessageBox.Show("密码错误"); }
 else
 {
 MessageBox.Show("登陆成功！");
 dengluzt();
 gkfm fm = new gkfm();
 fm.add (Convert.ToString(textBox1.Text));
 fm.Show();
 //this.Hide();
 }
 }
 catch (Exception ee)
 {
 MessageBox.Show(ee.Message);
 }

 

 }
 else
 if (dlsf == 1)
 {
 if (textBox1.Text.Trim() == "1" && textBox2.Text.Trim() == "1")
 {
 MessageBox.Show("登录成功");
 sjfm fm = new sjfm();
 fm.Show();
 // this.Hide();
 }
 else { MessageBox.Show("账号或密码错误！请重新输入！"); return; }
 }

 }
 private void label3_Click(object sender, EventArgs e)
 {
 zcfm fm = new zcfm();
 fm.Show();
 this.Hide();
 }
 }
}

注册界面

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace MenuSystemWss
{
 public partial class zcfm : Form
 {
 BaseInfo baseinfo = new BaseInfo();//
 BaseInfo.GkInfo gkinfo = new BaseInfo.GkInfo();//
 /* SqlConnection sqlcon;
 SqlCommand sqlcom;*/
 public zcfm()
 {
 InitializeComponent();
 }

 private void label6_Click(object sender, EventArgs e)
 {
 Form1 fm = new Form1();
 fm.Show();
 this.Hide();
 }

 private void button1_Click(object sender, EventArgs e)
 {
 if (textBox1.Text.Trim() == "" || textBox1.Text.Length != 11)
 {
 MessageBox.Show( "手机号错误，请规范填写");
 }
 else
 if (textBox2.Text.Trim() == "")
 {
 MessageBox.Show("用户名错误，请规范填写4-8位");
 }
 else
 if (textBox3.Text.Trim() == "" || textBox3.Text.Length < 6 || textBox3.Text.Length > 8)
 {
 MessageBox.Show("密码错误，请规范填写6-8位！");
 }
 else
 if (textBox4.Text.Trim() == "")
 {
 MessageBox.Show("密码错误，请规范填写6-8位!");
 }
 else
 if (textBox3.Text.Trim() != textBox4.Text.Trim())
 {
 MessageBox.Show("两次输入密码必须一致!");
 }
 else
 {

 try
 {
  gkinfo.Gk_num = textBox1.Text.Trim();
  gkinfo.Gk_name = textBox2.Text.Trim();
  gkinfo.Gk_pw = textBox3.Text.Trim();
  gkinfo.Gk_apw = textBox4.Text.Trim();
  gkinfo.Gk_zt = 0;
  int id = baseinfo.AddGk(gkinfo);
  MessageBox.Show("注册成功！", "成功提示！", MessageBoxButtons.OK, MessageBoxIcon.Information);
 }
 catch (Exception ee){ MessageBox.Show(ee.Message); }
 }
 }

 private void zcfm_Load(object sender, EventArgs e)
 {

 }
 }
}