C#

string sql = "SELECT TempIn, tempOut, humidity FROM Environmnets WHERE DateT > DateADD(mi, -30, Current_TimeStamp)  INNER JOIN TDevice ON Environmnets.Deviceid = TDevice.id INNER JOIN TMushroomHouse ON TDevice.MushroomHouseId = TMushroomHouse.id WHERE TMushroomHouse.id = @id";
              using (SqlConnection con = new SqlConnection(strConnString))
              using (SqlCommand cmd = new SqlCommand(sql, con))
              {
                  cmd.Parameters.AddWithValue("@id", DropDownList1.Text);

                  con.Open();

                  using (SqlDataReader dr = cmd.ExecuteReader())
                  {
                      while (dr.Read())
                      {
                          TempInTextBox.Text = dr.GetValue(0).ToString();
                          TempOutTextBox.Text = dr.GetValue(1).ToString();
                          HumidTextBox.Text = dr.GetValue(2).ToString();


                          Chart1.Series["TempIn"].Points.AddXY(DateTime.Now.ToShortTimeString(), Double.Parse(TempInTextBox.Text));
                          Chart1.Series["TempOut"].Points.AddXY(DateTime.Now.ToShortTimeString(), Double.Parse(TempOutTextBox.Text));
                          Chart1.Series["Humidity"].Points.AddXY(DateTime.Now.ToShortTimeString(), Double.Parse(HumidTextBox.Text));
                          Chart1.ChartAreas["ChartArea1"].Area3DStyle.Enable3D = true;
                      }
                      con.Close();

/*To simplify the explanation of the problem, i am using a very small portion of the code which the problem occurs. While attempting to read bytes from a large file, I am getting OutOfMemory errors. I don't want to buffer, store or save the bytes I am reading. I simply want to read each byte, then discard it completely (to free up the memory and prevent getting the error) and then read the next byte and so on to the end. I am not sure of HOW OR WHERE to to do my deletion of the bytes after they are read. I have been reading about "flush" but I am not sure of how to use it or even if it will work. Can someone please assist?*/
using System;
using System.IO;
using System.Collections;

namespace Applica
{
    class Program
    {
        static void Main(string[] args)
        {
            DirectoryInfo da = new DirectoryInfo("C:\\Folder");
            FileInfo[] Arr = da.GetFiles();
            if (Arr.Length == 0)
            {
                throw new InvalidOperationException("No files found.");
            }
            FileInfo ap = Arr[Arr.Length - 1];
            long Totbyte = ap.Length;
            string filePath = ap.FullName;
            string temPath = Path.GetTempFileName();
            byte[] data = File.ReadAllBytes(filePath);
            //File.WriteAllBytes(temPath, data);
        }
    }
}

namespace Task_Compare
{
    public partial class Form1 : Form
    {

        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {

            string data = "";
            Task Tf1 = Task.Factory.StartNew(() =>
                                  {
                                      data = GetData();
                                  });

            Task T2 = Tf1.ContinueWith((previousTask) =>
                                   {
                                      listBox1.Items.Insert(0, data);
                                   }, TaskScheduler.FromCurrentSynchronizationContext());

        }

        private void button2_Click(object sender, EventArgs e)
        {
            string data = "";
            Task Tf2 = Task.Factory.StartNew(() =>
                                    {
                                        data = GetData();
                                    });
            Tf2.Wait();

            listBox1.Invoke(new EventHandler(delegate
            {
                listBox1.Items.Insert(0, data);
            }));
        }

        private string GetData()
        {
            string temp = "";
            {
                temp = " Do something long running ......";
            }

            return temp;
        }
    }
}