detect screensaver in vb.net

Posted on 2009-04-06
Medium Priority
Last Modified: 2012-05-06

I'm using VB.NET 2008 & WinForms. I need a function that returns True if the system screensaver is running.

I have tried this:

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 Shared Function IsScreenSaverRunning() As Boolean
        Dim Running As Integer
        Const SPI_GETSCREENSAVEACTIVE As Integer = 16
        SystemParametersInfo(SPI_GETSCREENSAVEACTIVE, 0, Running, 0)
        Return Running
    End Function

But SystemParametersInfo returns an error value and after callin GetLastError I ger error 998 (Invalid access to memory location).

I guess the problem is with the API calling / passing parameters.

Any ideas?

Question by:rettiseert
LVL 86

Accepted Solution

Mike Tomlinson earned 1000 total points
ID: 24083507
This worked for me...

Note that I'm using SPI_GETSCREENSAVERRUNNING and the third parameter is being passed ByRef instead of ByVal:
Public Class Form1
    Private Const SPI_GETSCREENSAVERRUNNING As Integer = &H72
    Private Declare Function SystemParametersInfo Lib "user32" Alias "SystemParametersInfoA" _
        (ByVal uiAction As Integer, ByVal uiParam As Integer, ByRef pvParam As Integer, ByVal fWInIni As Integer) As Boolean
    Public Shared Function IsScreenSaverRunning() As Boolean
        Dim bRunning As Boolean
        SystemParametersInfo(SPI_GETSCREENSAVERRUNNING, 0, bRunning, False)
        Return bRunning
    End Function
    Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
        If Form1.IsScreenSaverRunning Then
        End If
    End Sub
End Class

Open in new window

LVL 13

Author Closing Comment

ID: 31567311
Wonderful, thank you.

Featured Post

Free Tool: Path Explorer

An intuitive utility to help find the CSS path to UI elements on a webpage. These paths are used frequently in a variety of front-end development and QA automation tasks.

One of a set of tools we're offering as a way of saying thank you for being a part of the community.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

Join & Write a Comment

This tutorial demonstrates one way to create an application that runs without any Forms but still has a GUI presence via an Icon in the System Tray. The magic lies in Inheriting from the ApplicationContext Class and passing that to Application.Ru…
Article by: Jorge
XML Literals are a great way to handle XML files and the community doesn’t use it as much as it should.  An XML Literal is like a String (http://msdn.microsoft.com/en-us/library/system.string.aspx) Literal, only instead of starting and ending with w…
In the video, one can understand the process of resizing images in single or bulk. Kernel Bulk Image Resizer is an easy to use tool for resizing large number of images. One can add and resize multiple images with this tool in single go. The video sh…
If you are looking for an automated tool which can generate reports for Outlook emails and other items from PST file, then you can go for Kernel PST Reporter tool. The reports which are created by this tool are helpful to analyze and understand PST …

597 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question