using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;

namespace WindowsFormsApplication1
{
 public partial class Form1 : Form
 {
 public Form1()
 {
 InitializeComponent();
 }
 [DllImport("winmm.dll")]
 //The mciSendString function sends a command string to an MCI device. The device that the command is sent to is specified in the command string.
 static extern Int32 mciSendString(String command, StringBuilder buffer, Int32 bufferSize, IntPtr hwndCallback);
 Boolean cdtrayopen = true;
 Boolean cdtrayclosed = false;
 private void Form1_Load(object sender, EventArgs e)
 {
 {
 if (DateTime.Now.Hour >= 1 && DateTime.Now.Hour <= 23)
 {
 timer1.Enabled = true;
 }
 else
 {
 MessageBox.Show("better u open at a correct time");
 }
 }
 }
 private void timer1_Tick(object sender, EventArgs e)
 {
 if (cdtrayopen == true)
 {
 //Inptr.Zero=A read-only field that represents a pointer or handle that has been initialized to zero.
 //function to open the CD tray door
 mciSendString("set CDAudio door open", null, 0, IntPtr.Zero);
 cdtrayopen = true;
 }
 else
 {
 //function to close the CD tray door
 mciSendString("set CDAudio door closed", null, 0, IntPtr.Zero);
 cdtrayopen = false;
 }
 timer1.Enabled = false;
 timer2.Enabled = true;
 }
 private void timer2_Tick(object sender, EventArgs e)
 {
 if (cdtrayclosed == false)
 {
 mciSendString("set CDAudio door closed", null, 0, IntPtr.Zero);
 cdtrayclosed = false;
 }
 else
 {
 mciSendString("set CDAudio door open", null, 0, IntPtr.Zero);
 cdtrayclosed = true;
 }
 timer2.Enabled = false;
 timer1.Enabled = true;
 }
 }
}

NOTE: This works only for desktops....it doesn't work for laptops.happy coding....