I got this program:
https://learn.microsoft.com/en-us/archive/blogs/toub/low-level-keyboard-hook-in-c
using System;
using System.Diagnostics;
using System.Windows.Forms;
using System.Runtime.InteropServices;
namespace KeyboardInput
{
class InterceptKeys
{
private delegate IntPtr LowLevelKeyboardProc(int nCode, IntPtr wParam, IntPtr lParam);
private const int WH_KEYBOARD_LL = 13;
private const int WM_KEYDOWN = 0x0100;
private static LowLevelKeyboardProc _proc = HookCallback;
private static IntPtr _hookID = IntPtr.Zero;
static void Main(string[] args)
{
_hookID = SetHook(_proc);
Application.Run();
UnhookWindowsHookEx(_hookID);
}
private static IntPtr SetHook(LowLevelKeyboardProc proc)
{
using (Process curProcess = Process.GetCurrentProcess())
using (ProcessModule curModule = curProcess.MainModule)
{
return SetWindowsHookEx(WH_KEYBOARD_LL, proc,
GetModuleHandle(curModule.ModuleName), 0);
}
}
private static IntPtr HookCallback(int nCode, IntPtr wParam, IntPtr lParam)
{
if (nCode >= 0 && wParam == (IntPtr)WM_KEYDOWN)
{
int vkCode = Marshal.ReadInt32(lParam);
Console.WriteLine((Keys)vkCode + " " + nCode + " " + wParam + " " + lParam);
}
return CallNextHookEx(_hookID, nCode, wParam, lParam);
}
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern IntPtr SetWindowsHookEx(int idHook, LowLevelKeyboardProc lpfn, IntPtr hMod, uint dwThreadId);
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
private static extern bool UnhookWindowsHookEx(IntPtr hhk);
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern IntPtr CallNextHookEx(IntPtr hhk, int nCode, IntPtr wParam, IntPtr lParam);
[DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern IntPtr GetModuleHandle(string lpModuleName);
}
}
It captures keyboard input, but what I want is to be able to differentiate between two keyboards. I'd like to know if the key pressed was from the keyboard on my laptop or the keyboard that's connected via an USB.
How do I accomplish this?
To distinguish between input devices, you may probably need to use Raw Input API
Here is a detailed example
UPDATE: The above link seems to be down. But here is a similar question answered by the blogger who provided above example.
Related
I am currently developing an operating system using the MOSA-OS compiler to compile CIL to machine code. Unfortunately, while developing an operating system it is not so simple to just "Console.ReadLine" to get input. Nothing from System.Console is working, and I can't use WinForms either. Is there an alternative way to get keypresses/input?
Hooking into the user32.dll is a great way. Here is a low-level keyboard listener that will do the job. All you need to do is call HookKeyboard() and listen for the OnKeyPressed event.
using System;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Windows.Input;
namespace DesktopWPFAppLowLevelKeyboardHook
{
public class LowLevelKeyboardListener
{
private const int WH_KEYBOARD_LL = 13;
private const int WM_KEYDOWN = 0x0100;
private const int WM_SYSKEYDOWN = 0x0104;
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern IntPtr SetWindowsHookEx(int idHook, LowLevelKeyboardProc lpfn, IntPtr hMod, uint dwThreadId);
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
private static extern bool UnhookWindowsHookEx(IntPtr hhk);
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern IntPtr CallNextHookEx(IntPtr hhk, int nCode, IntPtr wParam, IntPtr lParam);
[DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern IntPtr GetModuleHandle(string lpModuleName);
public delegate IntPtr LowLevelKeyboardProc(int nCode, IntPtr wParam, IntPtr lParam);
public event EventHandler<KeyPressedArgs> OnKeyPressed;
private LowLevelKeyboardProc _proc;
private IntPtr _hookID = IntPtr.Zero;
public LowLevelKeyboardListener()
{
_proc = HookCallback;
}
public void HookKeyboard()
{
_hookID = SetHook(_proc);
}
public void UnHookKeyboard()
{
UnhookWindowsHookEx(_hookID);
}
private IntPtr SetHook(LowLevelKeyboardProc proc)
{
using (Process curProcess = Process.GetCurrentProcess())
using (ProcessModule curModule = curProcess.MainModule)
{
return SetWindowsHookEx(WH_KEYBOARD_LL, proc, GetModuleHandle(curModule.ModuleName), 0);
}
}
private IntPtr HookCallback(int nCode, IntPtr wParam, IntPtr lParam)
{
if (nCode >= 0 && wParam == (IntPtr)WM_KEYDOWN || wParam == (IntPtr)WM_SYSKEYDOWN)
{
int vkCode = Marshal.ReadInt32(lParam);
if (OnKeyPressed != null) { OnKeyPressed(this, new KeyPressedArgs(KeyInterop.KeyFromVirtualKey(vkCode))); }
}
return CallNextHookEx(_hookID, nCode, wParam, lParam);
}
}
public class KeyPressedArgs : EventArgs
{
public Key KeyPressed { get; private set; }
public KeyPressedArgs(Key key)
{
KeyPressed = key;
}
}
}
I'm trying to write a simple app that counts every mouse click that occurs in Windows (left and right separated), not only within a form. So far i did not have any success in finding such solution. Thanks!
You will need to use the Win32 Hook API to capture mouse events. Stephen Toub provides a nice bit of sample code on his MSDN blog post about setting up a mouse hook.
class InterceptMouse
{
private static LowLevelMouseProc _proc = HookCallback;
private static IntPtr _hookID = IntPtr.Zero;
public static void Main()
{
_hookID = SetHook(_proc);
Application.Run();
UnhookWindowsHookEx(_hookID);
}
private static IntPtr SetHook(LowLevelMouseProc proc)
{
using (Process curProcess = Process.GetCurrentProcess())
using (ProcessModule curModule = curProcess.MainModule)
{
return SetWindowsHookEx(WH_MOUSE_LL, proc,
GetModuleHandle(curModule.ModuleName), 0);
}
}
private delegate IntPtr LowLevelMouseProc(int nCode, IntPtr wParam, IntPtr lParam);
private static IntPtr HookCallback(
int nCode, IntPtr wParam, IntPtr lParam)
{
if (nCode >= 0 &&
MouseMessages.WM_LBUTTONDOWN == (MouseMessages)wParam)
{
MSLLHOOKSTRUCT hookStruct = (MSLLHOOKSTRUCT)Marshal.PtrToStructure(lParam, typeof(MSLLHOOKSTRUCT));
Console.WriteLine(hookStruct.pt.x + ", " + hookStruct.pt.y);
}
return CallNextHookEx(_hookID, nCode, wParam, lParam);
}
private const int WH_MOUSE_LL = 14;
private enum MouseMessages
{
WM_LBUTTONDOWN = 0x0201,
WM_LBUTTONUP = 0x0202,
WM_MOUSEMOVE = 0x0200,
WM_MOUSEWHEEL = 0x020A,
WM_RBUTTONDOWN = 0x0204,
WM_RBUTTONUP = 0x0205
}
[StructLayout(LayoutKind.Sequential)]
private struct POINT
{
public int x;
public int y;
}
[StructLayout(LayoutKind.Sequential)]
private struct MSLLHOOKSTRUCT
{
public POINT pt;
public uint mouseData;
public uint flags;
public uint time;
public IntPtr dwExtraInfo;
}
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern IntPtr SetWindowsHookEx(int idHook,
LowLevelMouseProc lpfn, IntPtr hMod, uint dwThreadId);
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
private static extern bool UnhookWindowsHookEx(IntPtr hhk);
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern IntPtr CallNextHookEx(IntPtr hhk, int nCode,
IntPtr wParam, IntPtr lParam);
[DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern IntPtr GetModuleHandle(string lpModuleName);
}
In your code you would set this up to record WM_LBUTTONDOWN and WM_RBUTTONDOWN events.
While my C# WinForms app is running, I need to detect when the mouse pointer is moved over a 3rd party application.
I've done some Google'ing but I can't seem to find a useful code example that shows how to set up a Hook Procedure to another application using C# to detect Windows Messages.
Can someone please show me how to setup a C# hook procedure so I can detect the WM_MOUSEMOVE message on another app (e.g. Notepad.exe)?
Below is the C# Low Level Mouse Hook code I was looking for, from the blogs.msdn.com/b/toub/archive/2006/05/03/589468.aspx link (that David Heffernan posted)
class InterceptMouse
{
private static LowLevelMouseProc _proc = HookCallback;
private static IntPtr _hookID = IntPtr.Zero;
public static void Main()
{
_hookID = SetHook(_proc);
Application.Run();
UnhookWindowsHookEx(_hookID);
}
private static IntPtr SetHook(LowLevelMouseProc proc)
{
using (Process curProcess = Process.GetCurrentProcess())
using (ProcessModule curModule = curProcess.MainModule)
{
return SetWindowsHookEx(WH_MOUSE_LL, proc,
GetModuleHandle(curModule.ModuleName), 0);
}
}
private delegate IntPtr LowLevelMouseProc(int nCode, IntPtr wParam, IntPtr lParam);
private static IntPtr HookCallback(
int nCode, IntPtr wParam, IntPtr lParam)
{
if (nCode >= 0 &&
MouseMessages.WM_LBUTTONDOWN == (MouseMessages)wParam)
{
MSLLHOOKSTRUCT hookStruct = (MSLLHOOKSTRUCT)Marshal.PtrToStructure(lParam, typeof(MSLLHOOKSTRUCT));
Console.WriteLine(hookStruct.pt.x + ", " + hookStruct.pt.y);
}
return CallNextHookEx(_hookID, nCode, wParam, lParam);
}
private const int WH_MOUSE_LL = 14;
private enum MouseMessages
{
WM_LBUTTONDOWN = 0x0201,
WM_LBUTTONUP = 0x0202,
WM_MOUSEMOVE = 0x0200,
WM_MOUSEWHEEL = 0x020A,
WM_RBUTTONDOWN = 0x0204,
WM_RBUTTONUP = 0x0205
}
[StructLayout(LayoutKind.Sequential)]
private struct POINT
{
public int x;
public int y;
}
[StructLayout(LayoutKind.Sequential)]
private struct MSLLHOOKSTRUCT
{
public POINT pt;
public uint mouseData;
public uint flags;
public uint time;
public IntPtr dwExtraInfo;
}
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern IntPtr SetWindowsHookEx(int idHook,
LowLevelMouseProc lpfn, IntPtr hMod, uint dwThreadId);
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
private static extern bool UnhookWindowsHookEx(IntPtr hhk);
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern IntPtr CallNextHookEx(IntPtr hhk, int nCode,
IntPtr wParam, IntPtr lParam);
[DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern IntPtr GetModuleHandle(string lpModuleName);
}
I made a simple hook keyboard in C#, so i have this following code :
private static IntPtr hKeyboardHook = IntPtr.Zero;
private const int WH_KEYBOARD_LL = 13;
private const int WM_KEYDOWN = 0x100;
private delegate IntPtr LowLevelKeyboardProc(int nCode, IntPtr wParam, IntPtr lParam);
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern IntPtr SetWindowsHookEx(int idHook, LowLevelKeyboardProc lpfn, IntPtr hMod, uint dwThreadId);
[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall, SetLastError = true)]
private static extern int UnhookWindowsHookEx(IntPtr idHook);
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern IntPtr CallNextHookEx(IntPtr hhk, int nCode, IntPtr wParam, IntPtr lParam);
[DllImport("user32")]
private static extern int ToAscii(int uVirtKey, int uScanCode, byte[] lpbKeyState, byte[] lpwTransKey, int fuState);
[DllImport("user32")]
private static extern int GetKeyboardState(byte[] pbKeyState);
[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
private static extern short GetKeyState(int vKey);
private delegate int HookProc(int nCode, int wParam, IntPtr lParam);
[DllImport("kernel32.dll")]
public static extern IntPtr GetModuleHandle(string lpModuleName);
private static LowLevelKeyboardProc _proc = HookCallback;
public void initialization()
{
using (Process curProcess = Process.GetCurrentProcess())
using (ProcessModule curModule = curProcess.MainModule)
{
hKeyboardHook = SetWindowsHookEx(WH_KEYBOARD_LL, _proc, GetModuleHandle(curModule.ModuleName), 0);
}
}
private static IntPtr HookCallback(int nCode, IntPtr wParam, IntPtr lParam)
{
if (nCode >= 0 && wParam == (IntPtr)WM_KEYDOWN)
{
int vkCode = Marshal.ReadInt32(lParam);
if (vkCode >= 32 && vkCode < 160)
Console.Write((Keys)vkCode);
if (vkCode == 13)
Console.WriteLine("\n");
}
return CallNextHookEx(hKeyboardHook, nCode, wParam, lParam);
}
It works fine with no problem !! my program grip all key pressed in other program and write it on the console.
But i want to have the name of the program where the key is pressed, and i don't know how i can do that.
Anyone can help me ?
You are using a low-level hook (WH_KEYBOARD_LL). Low-level hooks are dispatched before the window manager decides which program will receive the message. Therefore, there is no "name of the program where the key is pressed" because the window manager hasn't yet decided which program the keypress will be delivered to. (You can try to guess by calling GetForegroundWindow.)
(Just curious: What is the ultimate problem you're trying to solve by using a keyboard hook? Maybe there's a better way. I hope you're not writing a keylogger.)
I will be grateful to anybody who could help!
I'm using the InterceptKeys class below to change some of the keys. For example when I type the open bracket key "[", I want to change this to "ë" (whenever I type in my computer, not a particular program).
I use a SendKey.Send("ë"); whenever the "[" is typed, but the problem is that after "ë" alsot the "[" is typed.
Is it possible to replace the "[" with "ë" or any key, or cancel the "[" and just send "ë"?
class InterceptKeys
{
private const int WH_KEYBOARD_LL = 13;
private const int WM_KEYDOWN = 0x0100;
private static LowLevelKeyboardProc _proc = HookCallback;
private static IntPtr _hookID = IntPtr.Zero;
public static void Main()
{
_hookID = SetHook(_proc);
Application.Run();
UnhookWindowsHookEx(_hookID);
}
private static IntPtr SetHook(LowLevelKeyboardProc proc)
{
using (Process curProcess = Process.GetCurrentProcess())
using (ProcessModule curModule = curProcess.MainModule)
{
return SetWindowsHookEx(WH_KEYBOARD_LL, proc,
GetModuleHandle(curModule.ModuleName), 0);
}
}
private delegate IntPtr LowLevelKeyboardProc(
int nCode, IntPtr wParam, IntPtr lParam);
private static IntPtr HookCallback(
int nCode, IntPtr wParam, IntPtr lParam)
{
if (nCode >= 0 && wParam == (IntPtr)WM_KEYDOWN)
{
int vkCode = Marshal.ReadInt32(lParam);
//Console.WriteLine((Keys)vkCode);
if (vkCode == (int)Keys.OemOpenBrackets))
{
SendKeys.Send("ë");
}
}
return CallNextHookEx(_hookID, nCode, wParam, lParam);
}
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern IntPtr SetWindowsHookEx(int idHook,
LowLevelKeyboardProc lpfn, IntPtr hMod, uint dwThreadId);
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
private static extern bool UnhookWindowsHookEx(IntPtr hhk);
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern IntPtr CallNextHookEx(IntPtr hhk, int nCode,
IntPtr wParam, IntPtr lParam);
[DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern IntPtr GetModuleHandle(string lpModuleName);
}
Return 1 if you handled the key instead of calling CallNextHookEx.
IE, HookCallback() should look like this
private static IntPtr HookCallback(
int nCode, IntPtr wParam, IntPtr lParam)
{
if (nCode >= 0 && wParam == (IntPtr)WM_KEYDOWN)
{
int vkCode = Marshal.ReadInt32(lParam);
//Console.WriteLine((Keys)vkCode);
if (vkCode == (int)Keys.OemOpenBrackets))
{
SendKeys.Send("ë");
return 1;
}
}
return CallNextHookEx(_hookID, nCode, wParam, lParam);
}