餐厅项目增加餐桌

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 餐厅
{
    public partial class Form1 : Form
    {



        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            LoadDeskInfoByDelFlag(0);

        }
        //数据库字符串
        string str = "Data Source=.;Initial Catalog=mysql;Integrated Security=True";
        private void LoadDeskInfoByDelFlag(int p)
        {
            //查询
            //新建集合
            List<DeskInfo> list = new List<DeskInfo>();

            //sql语句，flag为0的餐桌
            string sql = "select DeskId,DeskName,DeskNamePinYin,DeskNum from DeskInfo where DeskDelFlag = " + p;
            //string sql = "select * from DeskInfo";
            SqlConnection con = new SqlConnection(str);
            con.Open();
            SqlCommand cmd = new SqlCommand(sql, con);
            //cmd.reader为查询
            SqlDataReader reader = cmd.ExecuteReader();
            //判断是否读取了一行
            if (reader.HasRows)
            {
                //当读取的时候
                while (reader.Read())
                {
                    //实例化餐桌类，为每个属性赋值，值为数据库里的值，进行类型转换
                    DeskInfo dk = new DeskInfo();
                    dk.DeskId = Convert.ToInt32(reader["DeskId"]);
                    dk.DeskName = reader["DeskName"].ToString();
                    dk.DeskNamePinYin = reader["DeskNamePinYin"].ToString();
                    dk.DeskNum = reader["DeskNum"].ToString();
                    //把属性添加进list
                    list.Add(dk);
                }

            }
            //禁止自动生成列，没有delflag那一列了。
            dgv.AutoGenerateColumns = false;
            //绑定数据
            dgv.DataSource = list;

            //关闭数据库各项
            con.Dispose();
            cmd.Dispose();
            reader.Dispose();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            //增加餐桌 
            //sql语句
            string sql = string.Format("insert into DeskInfo(DeskName, DeskNamePinYin, DeskDelFlag, DeskNum) values('{0}','{1}',0,'{2}')", txtName.Text, txtPinYin.Text,txtNum.Text);
            SqlConnection con = new SqlConnection(str);
            con.Open();
            SqlCommand cmd = new SqlCommand(sql, con);
            cmd.ExecuteNonQuery();
            LoadDeskInfoByDelFlag(0);//刷新

            con.Dispose();
            cmd.Dispose();

        }
    }
}