I have a program that registers a certain hotkey combination for activation. For the purpose of this question, let's say this hotkey is Ctrl + Alt + D. Once the combination is pressed, my program will then simulate some other keyboard events to the active window using SendInput, for example, it could simulate Ctrl + A. My issue is that the simulation of Ctrl + A doesn't work properly since (I think) the Ctrl key is still pressed from the hotkey combination. One of the solutions I'm thinking to do is to send Key Up events for every key in my hotkey combination and then simulate Ctrl + A, however I wanted to check if this is the proper way of handling it?
First, understand that questions asking how to send keyboard messages are asked very often. I assume you have not invested much time looking for previous answers. Second, understand that beginners often mistakenly think that sending keyboard messages is the easiest and most effective solution. The truth is that it is usualy not the easiest and is not the most effective and not the most reliable.
If you are going to work with Windows messages like that, then learn to use Spy++. If you do not know what that is, then please invest a minute by familiarizing yourself with the tools available in the VS Tools menu.
A likely easier, more efective and reliable solution usually is to use the WM_GETTEXT and WM_SETTEXT messages. And anticipating future questions, to push a button in another application send a BN_CLICKED notification to the parent of the button. You can use Spy++ to get many more answers to questions of messages.
Using SendInput might be the best solution for you, but there is not enough of your requirements provided to say for sure. In my opinion, SendInput should be the last resort and used only when the other possibilities are not possible. Please spend some time reading some of the numerous articles and previous answers relevant to the question.
I have built an application which listens for a global hot key (Alt + Space currently), when I press the hot key when Google Chrome is in focus it brings my app to focus but also opens Chrome's context menu (right click menu). I used the following dll for implementing the keyboard hook.
Can I prevent this from happening? If so how? This isn't a major problem but if there is a way in which you can clear all existing hot keys tied to that combination then I'd like to learn this.
EDIT
The answer that I selected as being the correct one, is the correct one but for my problem. To correctly implement this feature into a C# WinForm i used this tutorial which was very helpful: http://www.dreamincode.net/forums/topic/180436-global-hotkeys/
The FAQ section of the linked article contains your answer:
Question
I need to suppress some keystrokes after I have processed them.
Answer
Just set the e.Handled property to true in the key events you have
processed. It prevents the keystrokes being processed by other
applications.
I'm working on an app (Written in C#) that have a setting to run on KIOSK mode. I've just an challenge here which is disabling Ctrl+Alt+Del combination Event.
There is no right answer in the similar past posts. Please let me know about the right action.
Considering, my code is working with registry keys to disable/enable options, if you know any registry key,it will be more helpful.
CTRL+ALT+DEL is the secure attention sequence of Windows NT (and its derivatives like Win7). It is the one key combination that is guaranteed to get the OS's attention. The whole point of the SAS is that it can't be intercepted or stopped by user programs.
One security issue it addresses is that of a false login screen: consider a screen that looks exactly like the normal Windows login screen. There's no way to tell that it's a fake just by looking at it. But, if you're in the habit of always pressing CTRL+ALT+DEL before logging in (there is an option to always require it for the legitimate screen), pressing the SAS on a false login screen will bring up task manager or the secure attention screen (with the log off, change password, etc options). The real login screen doesn't do that; it just stays there on the screen. As long as the OS itself isn't replaced or compromised, CTRL+ALT+DEL will protect you from false login screens. If a user program could intercept the SAS, it wouldn't be worth anything.
The SAS was baked into the Windows NT design right from the beginning (it was in the first release in 1993), so getting around it won't be easy. I'm sure there are keyboard filter drivers-- or something to intercept that sequence-- that are designed for kiosk use.
It is not possible to capture CTRL+ALT+DEL, it is so by design in all Windows systems. This is a security issue, if the user hits CTRL+ALT+DEL, he or she should be certain that it is the operating system and not some application (possibly a password-catching trojan) that responds to it.
I guess to capture CTRL+ALT+DEL you would need to write a device driver of some sorts.
Edit: Also see This answer. I did not try it, but the question is fairly similar.
Although it is sort of possible, it is not an easy task and not something that can be done in C#. This Article will show you how to disable CTRL+ALT+DEL using group policy editor. To permanently disable the combination though, you will either need to write your own keyboard driver or write your own GINA stub (Graphical Identification and Authentication).
It is possible to pick up the CTRL+ALT+DEL combination, but not to disable it.
I tried to disable it with SetWindowsHookEx and WH_KEYBOARD_LL and you can successfully get notified when CTRL+ALT+DEL is pressed, but you cannot do anything about it.
It is possible to block CTRL+ALT+DEL combination. However, you can't really disable it. As far as I know, there are two possible methods.
Remapping the keyboard layout. There is a registry binary key that allows you to remap keyboard layout:
HKLM\System\CurrentControlSet\Control\Keyboard Layout\Scancode Map
Please check this out: Disabling Windows Hot Keys
This method can be dangerous, but I haven't noticed any side effects this method can cause. The CTRL+ALT+DEL combination is handled by winlogon.exe. If your process has administrative privilege, you can suspend winlogon.exe. Hence, it cannot process the hotkey and nothing will happen if the user presses CTRL+ALT+DEL.
Please check this out: C++ code to disable CTRL+ALT+DEL.
You will need to do some P/Invoke, in user32.dll, there's a method called SystemParametersInfo, check out these resources for more info
http://pinvoke.net/search.aspx?search=SystemParametersInfo&namespace=[All]
http://msdn.microsoft.com/en-us/library/windows/desktop/ms724947%28v=vs.85%29.aspx
I did something similar a long while back, but no longer have the code, though I did find this (it's in vb6), but it shouldn't be too hard to get the idea and translate to .NET
http://www.developerfusion.com/code/1021/how-to-disable-ctrlaltdel/
I'm interested in extending the keys on the Windows keyboard (specifically - but not necessarily limited to - Windows 7). Currently I can use the keys available here in my C# application:
http://msdn.microsoft.com/en-us/library/system.windows.forms.keys(v=vs.71).aspx
What I'm interested in doing is extending the available keycodes so I can tailor them to my particular (programmable keyboard) hardware, and then be able to register these in my C#/DirectX applications. I know it is possible to create hotkey combinations, but I'd like to explore this option first. My questions are:
A) is this approach completely crazy?
B) if A == false: has anyone had any
practical experience with this. Can
you recommend any good
keywords/tutorials that I should be
looking at?
It is my understanding that Windows only accepts mouse/keyboard input based on the Keys enumeration (Virtual-keys in the unmanged world: http://msdn.microsoft.com/en-us/library/dd375731(v=vs.85).aspx). This makes your option A impossible to do on Windows.
As a concrete example Windows only has codes for five mouse buttons (LButton, RButton, MButton, XButton1, XButton2) but you can purchase a mouse that comes with more than five buttons. New virtual-key codes for the extended buttons cannot be created on the fly. To get around this limitation mice like this come with software that allows you to program what a press of each button does. Generally you'll find options to bind the extended buttons to a single press of some other virtual-key code or even write more complex macros that combine multiple key presses.
In your application the best you will be able to do is ensure that you properly handle the full range of values (and modifier combinations) from the Keys enumeration. Then program your keyboard appropriately. This may mean taking advantage of some of the extended virtual-keys like BrowserForward to make a larger set of virtual-key codes immediately available or generating more complex macros to enter a quick succession of virtual-key codes.
I'm creating a utility for my mother-in-law in order to remap CTRL-C and CTRL-V commands to one signal button on her keyboard to assist with at home work. On the first press it will commit a COPY command. Next press will be a PASTE command. Since my little application won't be in focus I'll need the use of GetAsyncKeyState. Right now I'm attempting to map this all to the tilde key. How do I kill the tilde key from actually passing to the field selected and overwriting the data or appending itself to the pasted text? Could either use C# in any .NET framework or VB6 for this little applet.
I understand the answer I'm looking for could assist in creating malicious software so if anyone should feel the need to not share or delete this question then by all means do so. I'm looking for an answer to a real issue or situation. I know I could map to a none typing key like Scroll Lock or Caps Lock like some other utilities out there but both of these keys are used at this point in time and not quite an option.
You going to have to do a global keyboard hook (see VBAccelerator for some details on global hooks in VB6), and then not pass on the message once you have received CTRL-V or CTRL-C and then act on that.