await async

        public Task<int> ExecuteAsync(MySqlConnection con, string sSQL)
        {
            return Task.Run(() =>
            {
                string constring = "Server = localhost; Database = jhcisdb;Port=3333; Uid = root; Pwd = 123456; AllowZeroDateTime = True;CharSet=utf8;default command timeout=100000";
                jcon = new MySqlConnection(constring);
                // using (var newConnection = new SqlConnection(sConnectionString))
                using (var newCommand = new MySqlCommand(sSQL, con))
                {
                    newCommand.CommandType = CommandType.Text;
                 

                    con.Open();
                    return newCommand.ExecuteNonQuery();
               
                }
            });
        }


//-------------------------------
        private async Task ExecuteSomeData()
        {
            //Use Async method to get data
            await ExecuteAsync(jcon, sqlAll);
         
        }
//----------------------------------------------
        private void BtnTest_Click(object sender, EventArgs e)
        {
             ExecuteSomeData();
            //MessageBox.Show("OK");
        }

Returning a column value from a table in dataset

https://stackoverflow.com/questions/23648132/returning-a-column-value-from-a-table-in-dataset

การจัดการ dateTimePicker

https://www.thaicreate.com/community/windows-form-datetimepicker.html


using System.Globalization;
using System.Threading;

            if (fromDate.Value.Date <= toDate.Value.Date)
            {
                CultureInfo _cultureEnInfo = new CultureInfo("en-US");

                DateTime dateBEgin = Convert.ToDateTime(this.fromDate.Value, _cultureEnInfo);
                DateTime dateEnd = Convert.ToDateTime(this.toDate.Value, _cultureEnInfo);
                //this.lblEng.Text = dateEng.ToString("dd MMM yyyy", _cultureEnInfo);
                this.lblEng.Text = dateBEgin.ToString("yyyy MM dd", _cultureEnInfo);
                lblEndate.Text = dateEnd.ToString("yyyy MM dd", _cultureEnInfo);

                lblXX.Text = getDate(fromDate);
                MessageBox.Show("OK");
            }
            else
            {
                MessageBox.Show("พ่องตาย");
            }

----------------------------------------------
        private string getDate(DateTimePicker d)
        {
            string xx;
            CultureInfo _cultureEnInfo = new CultureInfo("en-US");
            DateTime xDate = Convert.ToDateTime(d.Value, _cultureEnInfo);
            xx = xDate.ToString("yyyyMMdd", _cultureEnInfo);

            return xx;
        }