Registry settings immediate effect using C# - c#

I have used the following code to disable the control panel:
RegistryKey RegKey = Registry.CurrentUser.CreateSubKey(
#"Software\Microsoft\Windows\CurrentVersion\Policies\Explorer");
RegKey.SetValue("NoControlPanel", false, RegistryValueKind.DWord);
RegKey.Close();
The above code disables control panel only after restarting, I would like to apply the setting immediately without restarting. Please help me.

Try this...
private const int HWND_BROADCAST = 0xffff;
private const int WM_WININICHANGE = 0x001a, WM_SETTINGCHANGE = WM_WININICHANGE, INI_INTL = 1;
SendMessage(HWND_BROADCAST, WM_SETTINGCHANGE, 0, INI_INTL);
[DllImport("user32.dll")]
private static extern int SendMessage(int hWnd, uint wMsg, uint wParam, uint lParam);
This will notify all applications that changes have been made to the registry, and those programs that accept the notification shuould reload their settings.
Note that not all applications may do this, but things like control panel should.

I haven't tested this, but I suspect you only have to close all your explorer.exe processes for this to take effect.
Note that the desktop and taskbar are provided by explorer.exe, so you'll need to start a new one after closing them all.
It's a bit hostile, because the user might have Explorer windows that they don't want to lose, so do it only if it's not going to annoy people. 8-)

Related

Permanently hide or move taskbar off screen windows 10 LTSB ENT

We need to hide the taskbar and start menu. We have an app that runs full screen, it is a touch screen application. Our touch screen application is 99.9999% always on screen, covering the entire screen. It is however a complex multimedia app and on rare occasions we have found it crashed exposing the desktop. We have a custom made Win10 LTSB ENT build which is robust and appropriate, but we want to go a step further. We want to remove the taskbar (which is 'hidden') from the desktop entirely.
We can hide the taskbar using the code below, but it keeps returning 5 seconds later. Something keeps undoing our 'hide' and restoring the taskbar without us doing anything.
Am I doing something wrong? Is there a service or mechanism in Windows OS I need to adjust?
private static void setTaskBar(bool hide)
{
IntPtr window = Program.FindWindow("Shell_traywnd", "");
if (hide)
Program.SetWindowPos(window, IntPtr.Zero, 0, 0, 0, 0, 128U);
else
Program.SetWindowPos(window, IntPtr.Zero, 0, 0, 0, 0, 64U);
[DllImport("user32", SetLastError = true)]
private static extern IntPtr FindWindowEx(
IntPtr hWndl,
IntPtr hWnd2,
string lpsz1,
string lpsz2);
}
[DllImport("user32")]
private static extern bool SetWindowPos(
IntPtr hWndl,
IntPtr hWndInsertAfter,
int X,
int Y,
int cx,
int cy,
uint uFlags);
The taskbar is somewhat special, it receives messages from the window manager when other windows go in and out of fullscreen etc and adjusts itself accordingly.
Messing with the shell is the wrong solution. A better solution would be to launch another instance of your program that only has a fullscreen window and does nothing but waiting for the real instance to crash and then restart it if desired.

c# What are these volume changing codes/messages

I found this script to change the System sound volume and it works. But what are these constant volume codes called and where can I find a full list of these codes that do more things.
[DllImport("user32.dll")]
static extern IntPtr SendMessage(IntPtr hWnd, int Msg, IntPtr wParam, IntPtr lParam);
//Volume codes, or messages, or whatever they are called
const int VOLUME_MUTE = 0x80000;
const int VOLUME_DOWN = 0x90000;
const int VOLUME_UP = 0xA0000;
SendMessage(this.Handle, 0x319, IntPtr.Zero, (IntPtr)VOLUME_UP);
These are AppCommand messages.
0x319 is the Win32 Windows MSG for WM_APPCOMMAND, and the messages are more accurately APPCOMMAND_VOLUME_UP, etc...
AppCommand messages are messages sent to windows, which are handled at a global level and perform certain application functions. These tend to be linked to Keyboard hotkeys and mouse button functions.
Your app gets first crack at processing any such messages, and if you do not handle them then your apps parent does. If that doesn't handle them, then eventually it gets sent to a global message hook to process them. The key point here is that other windows can trap these messages, so it's not a guarantee that sending these messages will accomplish the task. Just like you might have seen where pressing the volume up or down on your keyboard might not always work when certain windows have focus.
You can find the details for all the messages in the Win32 API reference:
http://msdn.microsoft.com/en-us/library/windows/desktop/ms646275(v=vs.85).aspx

SendMessage() only working when window is open, not when minimized

I've been using SendMessage to send mouse clicks to a couple of windows. One being a game(everything works perfectly), but the other window, being a 3rd party tool for the game is having trouble with SendMessage. If the window is 'not minimized' everything works fine, don't matter if window is completely covered up by another. But if that same window is minimized then nothing happens, I checked with spy++ and the messages are indeed getting received but not being processed (correct term?). I've tried to solve this last couple days, doing both searches on here and Google alike, many of topics but nothing helped?
//MyImports
[DllImport("user32.dll", CharSet = CharSet.Auto)]
static extern IntPtr SendMessage(IntPtr hWnd, UInt32 Msg, IntPtr wParam, IntPtr lParam);
[DllImport("user32.dll", SetLastError = true)]
static extern IntPtr FindWindow(string lpClassName, string lpWindowName);
And this is how I have it wrapped
public static void LClick(string windowclass, int x, int y)
{
IntPtr WHandle = FindWindow(windowclass, null);
SendMessage(WHandle, (int)WMessages.WM_LBUTTONDOWN, (IntPtr)1, (IntPtr)MakeLParam(x, y));
SendMessage(WHandle, (int)WMessages.WM_LBUTTONUP, (IntPtr)0, (IntPtr)MakeLParam(x, y));
}
I have tried focus, activate. One thing that might be useful info is that the third party program is being loaded as module("Qt5QWindowIcon") of the game.
I tried PostMessage as well, and it does the same thing as SendMessage() same problem when minimized.
This game does allow for macroing and unattended macroing, Hints the third part tool designed to execute the macros (published by the creators) I'm just trying to simulate a mouse click on the program to start the macro.
I would just use SendInput, but the entire purpose of my program is to run in background.
I 've faced same problem .Please change assembly name and project name (Changed name not started with name on that you are throwing/posting windows message)then rebuild it and check it. Now you will able to debug.

Is it possible to completely prevent multiple instance on .NET Compact Framework?

Since I've try many ways to stop the multiple instance problem on handheld device which running on .net compact framework 3.5.
Currently , I got the solution by create "Mutex" and check if there is the same process is running. I put this statement in "Program.cs" which will executed at first time when program start.
But i think it's not shoot my problems cause I got request from user that they need to disable the "program icon" while it's running.
I understand the user's point that sometime they maybe "Open" the program multiple times or more within short period. So , If it still able to "Open". That mean the program will need to initial itself and maybe going fail finally. Is it possible to absolutely prevent the multiple instance ? or is there another way without programming like edit the registry on Windows CE ?
Here is my source code:
bool firstInstance;
NamedMutex mutex = new NamedMutex(false, "MyApp.exe", out firstInstance);
if (!firstInstance)
{
//DialogResult dialogResult = MessageBox.Show("Process is already running...");
Application.Exit();
}
NamedMutex is class from OpenNetCF.
Your code is almost fine. only missing thing is to remove the application exit and put in there the code needed to bring current running instance on top. i did this in the past so you do not need to disable or hide the icon you simply detect the already running instance and bring it on foreground.
Edit:
here some code snippet:
[DllImport("coredll.dll")]
private static extern IntPtr FindWindow(IntPtr className, string windowName);
[DllImport("coredll.dll")]
internal static extern int SetForegroundWindow(IntPtr hWnd);
[DllImport("coredll.dll")]
private static extern bool SetWindowPos(IntPtr hwnd, int hwnd2, int x,int y, int cx, int cy, int uFlags);
if (IsInstanceRunning())
{
IntPtr h = FindWindow(IntPtr.Zero, "Form1");
SetForegroundWindow(h);
SetWindowPos(h, 0, 0, 0, Screen.PrimaryScreen.Bounds.Width,Screen.PrimaryScreen.Bounds.Height, 0x0040);
return;
}
check these links for more info...
http://www.nesser.org/blog/archives/56 (including comments)
What is the best way to make a single instance application in Compact Framework?

How to bring a window foreground using c#?

I am trying to bring a window foreground. I am using this code. But its not working. Could someone please help?
ShowWindowAsync(wnd.hWnd, SW_SHOW);
SetForegroundWindow(wnd.hWnd);
// Code from Karl E. Peterson, www.mvps.org/vb/sample.htm
// Converted to Delphi by Ray Lischner
// Published in The Delphi Magazine 55, page 16
// Converted to C# by Kevin Gale
IntPtr foregroundWindow = GetForegroundWindow();
IntPtr Dummy = IntPtr.Zero;
uint foregroundThreadId = GetWindowThreadProcessId(foregroundWindow, Dummy);
uint thisThreadId = GetWindowThreadProcessId(wnd.hWnd, Dummy);
if (AttachThreadInput(thisThreadId, foregroundThreadId, true))
{
BringWindowToTop(wnd.hWnd); // IE 5.5 related hack
SetForegroundWindow(wnd.hWnd);
AttachThreadInput(thisThreadId, foregroundThreadId, false);
}
if (GetForegroundWindow() != wnd.hWnd)
{
// Code by Daniel P. Stasinski
// Converted to C# by Kevin Gale
IntPtr Timeout = IntPtr.Zero;
SystemParametersInfo(SPI_GETFOREGROUNDLOCKTIMEOUT, 0, Timeout, 0);
SystemParametersInfo(SPI_SETFOREGROUNDLOCKTIMEOUT, 0, Dummy, SPIF_SENDCHANGE);
BringWindowToTop(wnd.hWnd); // IE 5.5 related hack
SetForegroundWindow(wnd.hWnd);
SystemParametersInfo(SPI_SETFOREGROUNDLOCKTIMEOUT, 0, Timeout, SPIF_SENDCHANGE);
}
Code Explained
Making a window the foreground window
requires more than just calling the
SetForegroundWindow API. You must
first determine the foreground thread
and attach it to your window, using
AttachThreadInput, then call
SetForegroundWindow. That way they can
share input states.
First I call GetForegroundWindow to
get the handle of the current
foreground window. Then a few calls to
GetWindowThreadProcessId retrieve the
threads associated with the current
foreground window and the window I
want to bring to the foreground. If
these threads are the same a simple
call to SetForegroundWindow is all
that is necessary. Otherwise, the
foreground thread is attached to the
window that I am bringing to the front
and detached from what was the current
foreground window. The
AttachThreadInput API handles this.
Content Taken from here
Thanks.
I've used this method before:
[DllImport("user32.dll")]
static extern bool SetForegroundWindow(IntPtr hWnd);
Process[] processes = Process.GetProcessesByName("processname");
SetForegroundWindow(processes[0].MainWindowHandle);
More information: http://pinvoke.net/default.aspx/user32.SetForegroundWindow
This code restores and set focus to a window:
[DllImport("User32.dll")]
static extern int SetForegroundWindow(IntPtr hWnd);
[DllImport("user32.dll")]
internal static extern bool SendMessage(IntPtr hWnd, Int32 msg, Int32 wParam, Int32 lParam);
static Int32 WM_SYSCOMMAND = 0x0112;
static Int32 SC_RESTORE = 0xF120;
And use it like this:
var proc = Process.GetProcessesByName("YourProgram").FirstOrDefault();
if (proc != null)
{
var pointer = proc.MainWindowHandle;
SetForegroundWindow(pointer);
SendMessage(pointer, WM_SYSCOMMAND, SC_RESTORE, 0);
}
In order for SetForegroundWindow to work consistently, you have to meet a few criteria. The first is your process that would run the command must be in the foreground. Only foreground process can make another process foreground. In order to make your process foreground first, you have to bring the main window to the front, if it is not. You minimise it first and then SetForegroundWindow it, to make it foreground. Now find the target process and bring it to the front
The steps are
Minimise the current window
SetForegroundWindow it
Find the target process
SetForegroundWindow it
I've got an example, though it's a slightly different use case.
You should use SetForegroundWindow. Also it may be interesting for you C# Force Form Focus
I'll be brief: Form.BringToFront()
As of Windows 7 these features dont behave quite so well. If there is an application such as Excel in front of the application you want to bring to the front then Windows 7 blocks this and flashes the window. You can set a registry timeout setting ForegroundLockTimeout=0 in HKEY_CURRENT_USER\Control Panel\Desktop but these is known as stealing focus. To set the behaviour of how XP "should" behave and will behave in Windows 7 by default you can create/set the value to 0x00030D40 (200000ms).
I'd like to know what is the preferred solution for trusted Windows applications. eg. If I trust application B to take focus when I double click something in Application A, and some other app is obscuring the window of Application B.

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