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How to keep your screen always on

Posted on January 2, 2015 by CooLMinE No comments

On most systems this can be configured by going to Control Panel --> Power Options --> Choose when to turn off the display, but there are always some situations that this solution will not suffice. As an exmaple, the last time I faced this problem, Active Directory’s settings were overriding my system’s settings, which caused my display to turn off every 5 minutes regardless of how much I tried to tweak it using the Power Options.

As a workaround I decided to create a small application that would just keep the screen from turning off. I decided to share it with you in case you ever find yourself in a similar position.

You can download the program here.

If you know a bit about programming you can take a look at the source code below that will give you an idea on how this is achieved.

using System;

using System.Runtime.InteropServices;

using System.Windows.Forms;

namespace ScreenAlwaysOn

{

static class Program

{

[DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]

static extern EXECUTION_STATE SetThreadExecutionState(EXECUTION_STATE esFlags);

[FlagsAttribute]

public enum EXECUTION_STATE : uint

{

ES_AWAYMODE_REQUIRED = 0x00000040,

ES_CONTINUOUS = 0x80000000,

ES_DISPLAY_REQUIRED = 0x00000002,

ES_SYSTEM_REQUIRED = 0x00000001

}

static NotifyIcon tIcon = new NotifyIcon();

[STAThread]

static void Main()

{

SetThreadExecutionState(EXECUTION_STATE.ES_CONTINUOUS | EXECUTION_STATE.ES_DISPLAY_REQUIRED);

ContextMenu menu = new ContextMenu();

menu.MenuItems.Add("Exit", delegate { Application.Exit(); });

tIcon.Icon = Properties.Resources.monitor;

tIcon.Text = "Screen Always On";

tIcon.ContextMenu = menu;

tIcon.Visible = true;

Application.ApplicationExit += Application_ApplicationExit;

Application.Run();

}

static void Application_ApplicationExit(object sender, EventArgs e)

{

tIcon.Dispose();

}

The theory behind this solution is very simple. We are using the SetThreadExecutionState windows function to notify the system that the screen should stay on.

Flags Descriptions
ES_AWAYMODE_REQUIRED (0x00000040)
Away mode should be used only by media-recording and media-distribution applications that must perform critical background processing on desktop computers while the computer appears to be sleeping. See Remarks.

ES_CONTINUOUS(0x80000000)
Informs the system that the state being set should remain in effect until the next call that uses ES_CONTINUOUS and one of the other state flags is cleared.

ES_DISPLAY_REQUIRED(0x00000002)
Forces the display to be on by resetting the display idle timer.

ES_SYSTEM_REQUIRED(0x00000001)
Forces the system to be in the working state by resetting the system idle timer.