[C#] Enable/ disable screen saver

[yyy]

Hello,

I'm trying to use SystemParametersInfo in order to disable/ enable the screen saver. I try this:

[DllImport("user32", CharSet=CharSet.Auto)]
  	private static extern bool SystemParametersInfo(int uAction, bool uParam, int lpvParam, int fuWinIni);
  
  [DllImport("user32", CharSet=CharSet.Auto)]
  	private static extern bool SystemParametersInfo(int uAction, int uParam, bool lpvParam, int fuWinIni);

private const int HWND_BROADCAST = 65535;
  private const int WM_SYSCOMMAND = 274;
  private const int SC_SCREENSAVE = 61760;
  private const int SPI_GETSCREENSAVETIMEOUT = 14;
 private const int SPI_SETSCREENSAVETIMEOUT = 15;
 private const int SPIF_UPDATEINIFILE = 1;
 private const int SPIF_SENDWININICHANGE = 2;
 private const int SPI_SETSCREENSAVEACTIVE = 17;
private const int SPI_GETSCREENSAVEACTIVE = 16;

bool IsActive;

SystemParametersInfo(SPI_GETSCREENSAVEACTIVE, 0, IsActive, 0);
// disable the screen saver if it is enabled
if(IsActive)
{
SystemParametersInfo(SPI_SETSCREENSAVEACTIVE, false, 0, 0);
}

But it doesn't work :( I'm not sure that the SystemParametersInfo is OK, and I don't know how to use SPI_GETSCREENSAVEACTIVE and SPI_SETSCREENSAVEACTIVE.

Can anybody please tell me how to use it ?

[Elagizy]

I use this code but in VB.net, try to convert it to C# ;)

Private Declare Function SystemParametersInfo Lib "user32" Alias "SystemParametersInfoA" (ByVal uAction As Integer, ByVal uParam As Integer, ByVal lpvParam As Integer, ByVal fuWinIni As Integer) As Integer
    Public Function ToggleScreenSaverActive(ByRef Active As Boolean) As Boolean
        Dim lActiveFlag As Integer
        Dim retvaL As Integer

        lActiveFlag = IIf(Active, 1, 0)
        retvaL = SystemParametersInfo(17, lActiveFlag, 0, 0)
        ToggleScreenSaverActive = retvaL > 0
    End Function


    ' On
        ToggleScreenSaverActive(True)


    ' Off
        ToggleScreenSaverActive(False)

[yyy]

Ok, thanks - that seems to work :) But I still don't know how to determine whether the screen saver is active or no :( I want to know how to use SPI_GETSCREENSAVEACTIVE.

Do you know how to do it ?

[yyy]

Ok, thanks - that seems to work :) But I still don't know how to determine whether the screen saver is active or no :( I want to know how to use SPI_GETSCREENSAVEACTIVE.

Do you know how to do it ?

[yyy]

Sorry - double post :blush:

Edited March 20, 2005 by yyy

[Elagizy]

ok try this code (C#), without using IsActive or False

' Deactivate Screen Saver
retval=SystemParametersInfo(SPI_SETSCREENSAVEACTIVE, 0, 0, 0)

' Activate Screen Saver
retval=SystemParametersInfo(SPI_SETSCREENSAVEACTIVE, 1, 0, 0)

[yyy]

I know how to do that - it works fine. This is not the problem.

My problem is that I want to GET the screen saver state so I'll know whether the screen saver is active or not.

For that I need to use SPI_GETSCREENSAVEACTIVE

Do you know how to use that ?

[Elagizy]

  yyy said:

I know how to do that - it works fine. This is not the problem.

My problem is that I want to GET the screen saver state so I'll know whether the screen saver is active or not.

For that I need to use SPI_GETSCREENSAVEACTIVE

Do you know how to use that ?

585642321[/snapback]

ok change it to the line :

Private Const SPI_GETSCREENSAVEACTIVE As Long = &H10

and give a try

[yyy]

No - I know that too. Nevermind - I've found the solution, I think.

I did it that way:

[DllImport("user32", CharSet=CharSet.Auto)]
 ?private static extern bool SystemParametersInfo(int uAction, int uParam, ref bool lpvParam, int fuWinIni

SystemParametersInfo(SPI_GETSCREENSAVEACTIVE, 0, ref IsActive, 0);

I had to add the ref before the bool to cause it get the value.

Thanks anyway :DD

[Elagizy]

great then :D

BTW, your code has the option to determine whether the screen saver is running or not :

Private Const SPI_GETSCREENSAVERRUNNING As Long = &H72

SystemParametersInfo SPI_GETSCREENSAVERRUNNING, 0, IsRunning, False