I wanted a way to know if the screen saver was running 9active) or if the screen / terminal was locked. The best way to find out is through the SystemParameterInfo class which is not provided to the .Net framework, so you have to make a call to the API for it. Now SPI has way more information than just whether the screen saver is running or if the terminal is locked, but that's all I need it for at the moment. I've included more info on how to use it at the end.
Here's some more information I was able to dig up regarding using SPI, including
the values for constants: SPI_GETACCESSTIMEOUT = 60 SPI_GETANIMATION = 72 SPI_GETBEEP = 1 SPI_GETBORDER = 5 SPI_GETDEFAULTINPUTLANG = 89 SPI_GETDRAGFULLWINDOWS = 38 SPI_GETFASTTASKSWITCH = 35 SPI_GETFILTERKEYS = 50 SPI_GETFONTSMOOTHING = 74 SPI_GETGRIDGRANULARITY = 18 SPI_GETHIGHCONTRAST = 66 SPI_GETICONMETRICS = 45 SPI_GETICONTITLELOGFONT = 31 SPI_GETICONTITLEWRAP = 25 SPI_GETKEYBOARDDELAY = 22 SPI_GETKEYBOARDPREF = 68 SPI_GETKEYBOARDSPEED = 10 SPI_GETLOWPOWERACTIVE = 83 SPI_GETLOWPOWERTIMEOUT = 79 SPI_GETMENUDROPALIGNMENT = 27 SPI_GETMINIMIZEDMETRICS = 43 SPI_GETMOUSE = 3 SPI_GETMOUSEKEYS = 54 SPI_GETMOUSETRAILS = 94 SPI_GETNONCLIENTMETRICS = 41 SPI_GETPOWEROFFACTIVE = 84 SPI_GETPOWEROFFTIMEOUT = 80 SPI_GETSCREENREADER = 70 SPI_GETSCREENSAVEACTIVE = 16 SPI_GETSCREENSAVETIMEOUT = 14 SPI_GETSERIALKEYS = 62 SPI_GETSHOWSOUNDS = 56 SPI_GETSOUNDSENTRY = 64 SPI_GETSTICKYKEYS = 58 SPI_GETTOGGLEKEYS = 52 SPI_GETWINDOWSEXTENSION = 92 SPI_GETWORKAREA = 48 SPI_ICONHORIZONTALSPACING = 13 SPI_ICONVERTICALSPACING = 24 SPI_LANGDRIVER = 12 SPI_SETACCESSTIMEOUT = 61 SPI_SETANIMATION = 73 SPI_SETBEEP = 2 SPI_SETBORDER = 6 SPI_SETCURSORS = 87 SPI_SETDEFAULTINPUTLANG = 90 SPI_SETDESKPATTERN = 21 SPI_SETDESKWALLPAPER = 20 SPI_SETDOUBLECLICKTIME = 32 SPI_SETDOUBLECLKHEIGHT = 30 SPI_SETDOUBLECLKWIDTH = 29 SPI_SETDRAGFULLWINDOWS = 37 SPI_SETDRAGHEIGHT = 77 SPI_SETDRAGWIDTH = 76 SPI_SETFASTTASKSWITCH = 36 SPI_SETFILTERKEYS = 51 SPI_SETFONTSMOOTHING = 75 SPI_SETGRIDGRANULARITY = 19 SPI_SETHIGHCONTRAST = 67 SPI_SETICONMETRICS = 46 SPI_SETICONS = 88 SPI_SETICONTITLELOGFONT = 34 SPI_SETICONTITLEWRAP = 26 SPI_SETKEYBOARDDELAY = 23 SPI_SETKEYBOARDPREF = 69 SPI_SETKEYBOARDSPEED = 11 SPI_SETLANGTOGGLE = 91 SPI_SETLOWPOWERACTIVE = 85 SPI_SETLOWPOWERTIMEOUT = 81 SPI_SETMENUDROPALIGNMENT = 28 SPI_SETMINIMIZEDMETRICS = 44 SPI_SETMOUSE = 4 SPI_SETMOUSEBUTTONSWAP = 33 SPI_SETMOUSEKEYS = 55 SPI_SETMOUSETRAILS = 93 SPI_SETNONCLIENTMETRICS = 42 SPI_SETPENWINDOWS = 49 SPI_SETPOWEROFFACTIVE = 86 SPI_SETPOWEROFFTIMEOUT = 82 SPI_SETSCREENREADER = 71 SPI_SETSCREENSAVEACTIVE = 17 SPI_SETSCREENSAVETIMEOUT = 15 SPI_SETSERIALKEYS = 63 SPI_SETSHOWSOUNDS = 57 SPI_SETSOUNDSENTRY = 65 SPI_SETSTICKYKEYS = 59 SPI_SETTOGGLEKEYS = 53 SPI_SETWORKAREA = 47
using
System.Runtime.InteropServices;
using
System.Threading;
using
log4net;
namespace
InternalInstantMessenger
{
///
<summary>
/// Summary
description for SystemParameterInfoWrapper.
///
</summary>
///
<remarks>
/// A lot of
this was found on
/// http://www.dotnet247.com/247reference/msgs/45/225361.asp
///note: this
will only work on win 2000 or higher, NT doesn't support the screensaver
running on SPI
///</remarks>
public class
SystemParameterInfoWrapper
{
public
static int
SPI_GETSCREENSAVEACTIVE = 16;
public
static int
SPI_GETSCREENSAVERRUNNING = 114;
private
static readonly
log4net.ILog log =
log4net.LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);
[DllImport("user32.dll", CharSet=CharSet.Auto)]
public
static extern
int SystemParametersInfo(int
uAction,int uParam,
ref int
lpvParam, int fuWinIni);
public
static bool
IsScreenSaverRunning()
{p; {
bool running =
false;
try
{
int
screenSaverRunning = -1;
// is the screen saver
running?
int ok =
SystemParametersInfo(SPI_GETSCREENSAVERRUNNING, 0,
ref
screenSaverRunning, 0);
if (ok != 0)
{
if (screenSaverRunning
!= 0)
{p; {
// screen saver is
running
running = true;
}
}
}
catch (Exception e)
{
log.Error("Exception while determining if
screensaver is running",e);
}
return running;
}
public
SystemParameterInfoWrapper()
{p; {
}
}
Retrieve information about the time-out period associated with the accessibility
features. uiParam must be the size of the ACCESSTIMEOUT structure. pvParam is an
ACCESSTIMEOUT structure receiving the time-out settings.
Win 95/98 only: Retrieve information about the animation effects associated with
the user's actions. uiParam must be 0. pvParam is an ANIMATIONINFO structure
receiving the animation effects settings.
Determine if the warning beeper is on or off. uiParam must be 0. pvParam is a
Long-type variable which receives 0 if the warning beeper is off, or a non-zero
value if it is on.
Retrieve the window sizing border multiplier factor, which determines the width
of a window's sizing border. uiParam must be 0. pvParam is a Long-type variable
which receives the current setting.
Win 95/98 only: Retrieve a handle to the keyboard layout used for the system's
default input language. uiParam must be 0. pvParam is a Long-type variable which
receives the handle.
Win 95/98 only: Determine if Windows displays the entire contents of a window
when it is moved or resized (instead of merely displaying an outline of it).
uiParam must be 0. pvParam is a Long-type variable which receives 0 if the
contents are not displayed, or a non-zero value if they are.
Determine if fast Alt-Tab task switching is enabled. uiParam must be 0. pvParam
is a Long-type variable which receives 0 if fast task switching is not enabled,
or a non-zero value if it is.
Retrieve the settings of the FilterKeys accessibility feature. uiParam must be
the size of the FILTERKEYS structure. pvParam is a FILTERKEYS structure which
receives the current settings of FilterKeys.
Determine whether font smoothing is enabled or not. uiParam must be 0. pvParam
is a Long-type variable which receives 0 if font smoothing is not enabled, or a
non-zero value if it is.
Retrieve the current granularity of the desktop sizing grid. uiParam must be 0.
pvParam is a Long-type variable which receives the current setting.
Win 95/98 only: Retrieve the settings of the HighContrast accessibility feature.
uiParam must be 0. pvParam is a HIGHCONTRAST structure which receives the
current settings of HighContrast.
Win 95/98 only: Retrieve the metrics associated with icons, which determine how
Windows displays icons. uiParam must be 0. pvParam is an ICONMETRICS structure
which receives the icon metrics.
Retrieve information about the logical font used to display the titles of icons.
uiParam must be the size of the LOGFONT structure. pvParam is a LOGFONT
structure which receives information about the logical font.
Determine if Windows word-wraps the text of icon titles. uiParam must be 0.
pvParam is a Long-type variable which receives 0 if word-wrapping is not
enabled, or a non-zero value if it is.
Retrieve the current keyboard repeat delay setting, which is the time before a
held key begins to repeat. uiParam must be 0. pvParam is a Long-type variable
which receives the current delay setting (a value between 0 and 3).
Win 95/98 only: Determine if the user relies on the keyboard instead of the
mouse and wants programs to display keyboard interfaces which are otherwise
hidden. uiParam must be 0. pvParam is a Long-type variable which receives 0 if
the user does not rely on the keyboard, or a non-zero value if the user does.
Retrieve the current keyboard repeat speed setting, which is the speed between
repeats when a key is held. uiParam must be 0. pvParam is a Long-type variable
which receives the current speed setting (a value between 0 and 31).
Win 95/98 only: Determine if the system enters a low-power mode after a period
of inactivity. uiParam must be 0. pvParam is a Long-type variable which receives
0 if low-power mode is not enabled, or a non-zero value if it is.
Win 95/98 only: Retrieve the time, in seconds, which must elapse before Windows
enters low-power mode. uiParam must be 0. pvParam is a Long-type variable which
receives the current timeout value.
Determine if popup menus are left- or right-aligned. uiParam must be 0. pvParam
is a Long-type variable which receives 0 if the menus are right-aligned, or a
non-zero value if they are left-aligned.
Win 95/98 only: Retrieve the metrics associated with minimized windows, which
specify how Windows displays minimized windows. uiParam must be the size of the
MINIMIZEDMETRICS structure. pvParam is a MINIMIZEDMETRICS structure which
receives the minimized window metrics.
Retrieve the x-axis and y-axis threshold values for the mouse as well as the
mouse speed. uiParam must be 0. pvParam is a 3-element array of Long-type
variables which receives the x-threshold, y-threshold, and mouse speed.
Retrieve the settings of the MouseKeys accessibility feature. uiParam must be
the size of the MOUSEKEYS structure. pvParam is a MOUSEKEYS structure which
receives the current settings of MouseKeys.
Win 95/98 only: Retrieve the current mouse trails setting. uiParam must be 0.
pvParam receives 0 or 1 if mouse trails are not enabled, or a value greater than
one identifying the number of cursor images making up the mouse trail.
Win 95/98 only: Retrieve the metrics associated with the nonclient areas of
windows, which determine how Windows renders nonclient areas. uiParam must be 0.
pvParam is a NONCLIENTMETRICS structure which receives the nonclient area
metrics.
Win 95/98 only: Determine if the system enters a power-off mode after a period
of inactivity. uiParam must be 0. pvParam is a Long-type variable which receives
0 if power-off mode is not enabled, or a non-zero value if power-off mode is
enabled.
Win 95/98 only: Retrieve the time-out value, in seconds, that must elapse before
Windows enters power-off mode. uiParam must be 0. pvParam is a Long-type
variable which receives the time-out value for power-off mode.
Win 95/98 only: Determine if a screen reader utility is running. If it is,
applications should present more textual output instead of graphical output to
help the reader function better. uiParam must be 0. pvParam is a Long-type
variable which receives 0 if no screen reader is running, or a non-zero value if
one is.
Determine if a screen saver is set to run. uiParam must be 0. pvParam is a
Long-type variable which receives 0 if no screen saver is set to run, or a
non-zero value if one is.
Retrieve the time-out period, in seconds, which must elapse before the screen
saver begins running. uiParam must be 0. pvParam is a Long-type variable which
receives the time-out value.
Win 95/98 only: Retrieve the settings of the SerialKeys accessibility feature.
uiParam must be 0. pvParam is a SERIALKEYS structure which receives the current
settings of SerialKeys.
Determine if the user desires visual information to replace or suppliment
otherwise audio-only output. uiParam must be 0. pvParam is a Long-type variable
which receives 0 if programs should not display this added visual information,
or a non-zero value if they should.
Retrieve the settings of the SoundSentry accessibility feature. uiParam must be
the size of the SOUNDSENTRY structure. pvParam is a SOUNDSENTRY structure which
receives the current settings of SoundSentry.
Retrieve the settings of the StickyKeys accessibility feature. uiParam must be
the size of the STICKYKEYS structure. pvParam is a STICKYKEYS structure which
receives the settings of StickyKeys.
Retrieve the settings of the ToggleKeys accessibility feature. uiParam must be
the size of the TOGGLEKEYS structure. pvParam is a TOGGLEKEYS structure which
receives the current settings of ToggleKeys.
Win 95/98 only: Determine if the Windows extensions are installed. Win 95
requires that Microsoft Plus! be installed to get the extensions; the extensions
are integrated as a part of Win 98. uiParam must be 1. pvParam must be 0. The
function returns 0 if the extensions are disabled, or a non-zero value if they
are enabled.
Win 95/98 only: Retrieve the size of the working area, which is a rectangle
identifying the area of the desktop not obscured by the taskbar. uiParam must be
0. pvParam is a RECT structure which receives the rectangle of the working area.
Set the width of the icon spacing cell. uiParam is the new setting for the
width. pvParam must be 0.
Set the height of the icon spacing cell. uiParam is the new setting for the
height. pvParam must be 0.
Win 95/98 only: Retrieve the filename of the language driver. uiParam must be 0.
pvParam is a String (with sufficient buffer space) which receives the filename
of the language driver.
Set information associated with the time-out period associated with the
accessibility features. uiParam must be the size of the ACCESSTIMEOUT structure.
pvParam is an ACCESSTIMEOUT structure holding the new time-out period settings.
Win 95/98 only: Set information about the animation effects associated with the
user's actions. uiParam must be 0. pvParam is an ANIMATIONINFO structure holding
the new animation effects settings.
Turn the warning beeper on or off. uiParam is 0 to turn the beeper off, or a
non-zero value to turn it on. pvParam must be 0.
Set the window sizing border multiplier factor, which determines the width of a
window's sizing border. uiParam is the new setting. pvParam must be 0.
Reload the images used for the system cursors. uiParam and pvParam must be 0.
Win 95/98 only: Set the keyboard layout used for the system's default input
language. uiParam is a handle to the keyboard layout to use. pvParam must be 0.
Set the current desktop pattern bitmap by causing Windows to reread the Pattern
setting in the [Desktop] section of WIN.INI. Both uiParam and pvParam must be 0.
Set the current desktop wallpaper bitmap. uiParam must be 0. pvParam is a String
holding the filename of the bitmap file to use as the wallpaper.
Set the time, in milliseconds, within which two successive mouse clicks must
occur for Windows to interpret the input to be a double click. uiParam is the
new double click time. pvParam must be 0.
Set the height of the rectangle within which two successive mouse clicks must
occur for Windows to interpret the input to be a double click. uiParam is the
new height. pvParam must be 0.
Set the width of the rectangle within which two successive mouse clicks must
occur for Windows to interpret the input to be a double click. uiParam is the
new width. pvParam must be 0.
Win 95/98 only: Turn dragging of full windows (displaying the contents of a
window while moving or resizing instead of just an empty border) on or off.
uiParam is 0 to turn dragging of full windows off, or a non-zero value to turn
it on.
Win 95/98 only: Set the height of the rectangle which the cursor must move out
of with a button depressed for Windows to begin a drag operation. uiParam is the
new height. pvParam must be 0.
Win 95/98 only: Set the width of the rectangle which the cursor must move out of
with a button depressed for Windows to begin a drag operation. uiParam is the
new width. pvParam must be 0.
Turn fast Alt-Tab task switching on or off. uiParam is 0 to turn fast switching
off, or a non-zero value to turn it on. pvParam must be 0.
Set the settings of the FilterKeys accessibility feature. uiParam must be the
size of the FILTERKEYS structure. pvParam is a FILTERKEYS structure holding the
new settings for FilterKeys.
Turn font smoothing on or off. uiParam is 0 to turn font smoothing off, or a
non-zero value to turn it on.
Set the granularity of the desktop sizing grid. uiParam is the new setting.
pvParam must be 0.
Win 95/98 only: Set the settings of the HighContrast accessibility feature.
uiParam must be 0. pvParam is a HIGHCONTRAST structure holding the new settings
for HighContrast.
Win 95/98 only: Set the metrics associated with icons, which specify how Windows
displays icons. uiParam must be 0. pvParam is an ICONMETRICS structure holding
the new icon metrics.
Reload the images used for the system icons. uiParam and pvParam must be 0.
Set the logical font used to display the text of icon titles. uiParam must be
the size of the LOGFONT structure. pvParam is a LOGFONT structure holding the
logical font to use.
Turn the word-wrapping of icon titles on or off. uiParam is 0 to turn
word-wrapping off, or a non-zero value to turn it on. pvParam must be 0.
Set the keyboard repeat-delay setting, which is the time that must elapse before
a held key begins to repeat. uiParam is the new delay setting, between 0 and 3
inclusive. pvParam must be 0.
Win 95/98 only: Tell Windows whether the user depends on the keyboard as the
main input device and wishes programs to display additional keyboard-based
interfaces. uiParam is 0 to not indicate a keyboard preference, or a non-zero
value to indicate one. pvParam must be 0.
Set the keyboard repeat-speed setting, which specifies the rate at which keys
are repeated. uiParam is the new speed setting, between 0 and 31 inclusive.
pvParam must be 0.
Win 95/98 only: Set the hot key used to switch keyboard input languages. The new
value is read from the registry at HKEY_CURRENT_USER\keyboard layout\toggle: 1
sets the hot key to ALT+SHIFT, 2 sets the hot key to CTRL+SHIFT, and 3 disables
the hot key. uiParam and pvParam must be 0.
Win 95/98 only: Turn the low-power mode after a period of inactivity on or off.
uiParam is 0 to deactivate low-power mode, or 1 to activate to. pvParam must be
0.
Win 95/98 only: Set the time-out period (in seconds) which must elapse after
user input before Windows enters low-power mode. uiParam is the new time-out
period. pvParam must be 0.
Set whether pop-up menus open to the left or to the right. uiParam is 0 if they
open to the left, or a non-zero value if they open to the right. pvParam must be
0.
Win 95/98 only: Set the metrics associated with minimized windows, which
determine how Windows displays minimized windows. uiParam must be 0. pvParam is
a MINIMIZEDMETRICS structure holding the new metrics.
Set the x-axis and y-axis threshold values for the mouse as well as the mouse
speed. uiParam must be 0. pvParam is a three-element Long-type array; the first
element is the x-threshold, the second element is the y-threshold, and the third
element is the mouse speed.
Swap or unswap the meanings of the left and right mouse buttons. uiParam is 0 to
restore the left-to-left/right-to-right mapping, or a non-zero value to swap the
buttons into a left-to-right/right-to-left mapping. pvParam must be 0.
Set the settings of the MouseKeys accessibility feature. uiParam must be the
size of the MOUSEKEYS structure. pvParam is a MOUSEKEYS structure holding the
new settings for MouseKeys.
Win 95/98 only: Set the length of the mouse trail. uiParam is 0 or 1 to turn
mouse trails off, or a value greater than one identifying the number of cursor
images used to make up the mouse trail. pvParam must be 0.
Win 95/98 only: Set the metrics associated with the non-client areas of windows,
which determine how Windows displays the non-client areas. uiParam must be 0.
pvParam is a NONCLIENTMETRICS structure holding the new metrics.
Win 95/98 only: Load or unload Microsoft Pen for Windows, if available. uiParam
is 0 to unload Pen, or a non-zero value to load Pen. pvParam must be 0.
Win 95/98 only: Set whether the system powers down after a period of inactivity.
uiParam is 0 to not enter power-off mode, or a non-zero value to enter power-off
mode. pvParam must be 0.
Win 95/98 only: Set the time-out period, in seconds, which must elapse without
user input before Windows enters power-off mode. uiParam is the new time-out
period. pvParam must be 0.
Win 95/98 only: Set whether a screen-reading program is currently running.
uiParam is 0 if no reader is in use, or a non-zero value if one is. pvParam must
be 0.
Set whether Windows activates a screen saver after a period of inactivity.
uiParam is 0 to turn the screen saver off, or a non-zero value to turn it on.
pvParam must be 0.
Set the time-out period, in seconds, which must elapse before Windows launches a
screen saver. uiParam is the new time-out period. pvParam must be 0.
Win 95/98 only: Set the settings of the SerialKeys accessibility feature.
uiParam must be 0. pvParam is a SERIALKEYS structure holding the new settings
for SerialKeys.
Turn the ShowSounds accessibility feature on or off. uiParam is 0 to turn
ShowSounds off, or a non-zero value to turn ShowSounds on. pvParam must be 0.
Set the settings of the SoundSentry accessibility feature. uiParam must be the
size of the SOUNDSENTRY structure. pvParam is a SOUNDSENTRY structure holding
the new settings for SoundSentry.
Set the settings of the StickyKeys accessibility feature. uiParam is the size of
the STICKYKEYS structure. pvParam is a STICKYKEYS structure holding the new
settings for StickyKeys.
Set the settings of the ToggleKeys accessibility feature. uiParam is the size of
the TOGGLEKEYS structure. pvParam is a TOGGLEKEYS structure holding the new
settings for ToggleKeys.
Win 95/98 only: Set the rectangle defining the working area of the desktop. The
working area is the area of the desktop not obscured by the taskbar. uiParam
must be 0. pvParam is a RECT structure holding the new working area rectangle.