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SystemEvents.UserPreferenceChanging Event

  • Reference

Definition

Namespace:
Microsoft.Win32
Assembly:
Microsoft.Win32.SystemEvents.dll
Assembly:
System.dll
Package:
Microsoft.Win32.SystemEvents v9.0.0
Source:
SystemEvents.cs
Source:
SystemEvents.cs
Source:
SystemEvents.cs
Source:
SystemEvents.cs

Occurs when a user preference is changing.

public:
 static event Microsoft::Win32::UserPreferenceChangingEventHandler ^ UserPreferenceChanging;
public static event Microsoft.Win32.UserPreferenceChangingEventHandler? UserPreferenceChanging;
public static event Microsoft.Win32.UserPreferenceChangingEventHandler UserPreferenceChanging;
member this.UserPreferenceChanging : Microsoft.Win32.UserPreferenceChangingEventHandler 
Public Shared Custom Event UserPreferenceChanging As UserPreferenceChangingEventHandler

Event Type

UserPreferenceChangingEventHandler

Exceptions

InvalidOperationException

System event notifications are not supported under the current context. Server processes, for example, might not support global system event notifications.

ExternalException

The attempt to create a system events window thread did not succeed.

Examples

The following code example demonstrates how to monitor the UserPreferenceChanging event. This code example is part of a larger example provided for the SystemEvents class.

int main()
{
    // Set the SystemEvents class to receive event notification
    // when a user preference changes, the palette changes, or
    // when display settings change.
    SystemEvents::UserPreferenceChanging += gcnew
        UserPreferenceChangingEventHandler(
        SystemEvents_UserPreferenceChanging);
    SystemEvents::PaletteChanged += gcnew
        EventHandler(SystemEvents_PaletteChanged);
    SystemEvents::DisplaySettingsChanged += gcnew
        EventHandler(SystemEvents_DisplaySettingsChanged);

    // For demonstration purposes, this application sits idle
    // waiting for events.
    Console::WriteLine("This application is waiting for system events.");
    Console::WriteLine("Press <Enter> to terminate this application.");
    Console::ReadLine();
}

static void Main() 
{         
    // Set the SystemEvents class to receive event notification when a user 
    // preference changes, the palette changes, or when display settings change.
    SystemEvents.UserPreferenceChanging += new 
        UserPreferenceChangingEventHandler(SystemEvents_UserPreferenceChanging);
    SystemEvents.PaletteChanged += new 
        EventHandler(SystemEvents_PaletteChanged);
    SystemEvents.DisplaySettingsChanged += new 
        EventHandler(SystemEvents_DisplaySettingsChanged);        

    // For demonstration purposes, this application sits idle waiting for events.
    Console.WriteLine("This application is waiting for system events.");
    Console.WriteLine("Press <Enter> to terminate this application.");
    Console.ReadLine();
}

'Set the SystemEvents class to receive event notification 
'when a user preference changes, the palette changes, or 
'when display settings change.
AddHandler SystemEvents.UserPreferenceChanging, _
AddressOf SystemEvents_UserPreferenceChanging

AddHandler SystemEvents.PaletteChanged, _
AddressOf SystemEvents_PaletteChanged

AddHandler SystemEvents.DisplaySettingsChanged, _
AddressOf SystemEvents_DisplaySettingsChanged

Remarks

Note

This event is only raised if the message pump is running. In a Windows service, unless a hidden form is used or the message pump has been started manually, this event will not be raised. For a code example that shows how to handle system events by using a hidden form in a Windows service, see the SystemEvents class.

Caution

Because this is a static event, you must detach your event handlers when your application is disposed, or memory leaks will result.

Applies to

See also