Global Hook to detect keypresses?
Global Hook to detect keypresses?
Is a global hook the only way to detect key presses outside the main program window?
From what I read, a global hook must be contained inside a DLL which won't work for my current scenario.
From what I read, a global hook must be contained inside a DLL which won't work for my current scenario.
It doesn't need to be in a dll.. i Have an exe in assembly that hooks the keyboard.
Just pass the current Module Handle of your exe & the function pointer to your hook proc to SetWindowsHookEx (otherwise you may throw an error if that's NULL and the ThreadID is 0 as well)
Just pass the current Module Handle of your exe & the function pointer to your hook proc to SetWindowsHookEx (otherwise you may throw an error if that's NULL and the ThreadID is 0 as well)
Originally Posted by B1ackAnge1
It doesn't need to be in a dll.. i Have an exe in assembly that hooks the keyboard.
Just pass the current Module Handle of your exe & the function pointer to your hook proc to SetWindowsHookEx (otherwise you may throw an error if that's NULL and the ThreadID is 0 as well)
Just pass the current Module Handle of your exe & the function pointer to your hook proc to SetWindowsHookEx (otherwise you may throw an error if that's NULL and the ThreadID is 0 as well)
Lol well in a nutshell, a hook is a way for a function you write to 'intercept' a windows message/event that happens and process it before it gets to the window it's trying to get to. This way your hook callback function, which gets called by windows, can then process the command and do something with it, and in some cases even prevent the original target window from receiving it, or change the message before it reaches the target window.
For instance a Keypress normally works like this:
User presses Key-->OS Reacts--->Sends KeyPress Event-->Active Window-->Application processes keypress and does what it needs to.
If you 'register' a hook (by calling setwindowshookex) which basically tells windows "hey when this or that happens, call my function first", you get something like this:
User does KeyPress->OS-->Sends KeyPress Event--->HOOK CALLBACK gets called->You do whatever you want with it, for instance save to a file-->Message continues on to Active Window as if nothing happened etc.
That's the basics of a keylogger right there
Same thing with D3D hacks etc. they intercept the drawing events and change a few things around to give the user an advantage
For instance a Keypress normally works like this:
User presses Key-->OS Reacts--->Sends KeyPress Event-->Active Window-->Application processes keypress and does what it needs to.
If you 'register' a hook (by calling setwindowshookex) which basically tells windows "hey when this or that happens, call my function first", you get something like this:
User does KeyPress->OS-->Sends KeyPress Event--->HOOK CALLBACK gets called->You do whatever you want with it, for instance save to a file-->Message continues on to Active Window as if nothing happened etc.
That's the basics of a keylogger right there
Same thing with D3D hacks etc. they intercept the drawing events and change a few things around to give the user an advantage
Hey that makes beautiful sense! Now here is for something that i was actually confused about and not just ignorant =). Callbacks. I can't seem to find ANY explanations for/about them.
Hmm i'm gonna offer my guess as to what they are. Are they functions that you can set up so that when something happens, the callback function gets called, sort of like an event (don't remember which language this term is from)? I'm probably wrong though. =)
Hmm i'm gonna offer my guess as to what they are. Are they functions that you can set up so that when something happens, the callback function gets called, sort of like an event (don't remember which language this term is from)? I'm probably wrong though. =)
Originally Posted by zeco
Hey that makes beautiful sense! Now here is for something that i was actually confused about and not just ignorant =). Callbacks. I can't seem to find ANY explanations for/about them.
Hmm i'm gonna offer my guess as to what they are. Are they functions that you can set up so that when something happens, the callback function gets called, sort of like an event (don't remember which language this term is from)? I'm probably wrong though. =)
Hmm i'm gonna offer my guess as to what they are. Are they functions that you can set up so that when something happens, the callback function gets called, sort of like an event (don't remember which language this term is from)? I'm probably wrong though. =)
Can you explain what your problem is with GetAsyncKeyState? I don't see why you would want to get more complicated in regards to that.
Originally Posted by teat
Can you explain what your problem is with GetAsyncKeyState? I don't see why you would want to get more complicated in regards to that.
GetAsyncKeystate works fine outside the window o__O
Yes it does, and on the contrary I would be looking for something that would affect ONLY the window. Don't know why you are looking for something to affect all windows.
only 'bad' thing about getasynckeystate is that if another app calls it before your app you won't see it.
Ehh, I'm still having a ton of trouble using hooks.
What part are you sitll having issues with?
Originally Posted by B1ackAnge1
What part are you sitll having issues with?
Depending on whether or not you're using WH_KEYBOARD or WH_KEYBOARD_LL it's different.
if you using WH_KEYBOARD then the wparam in your callback will hold the virtual keycode whicih you can then compare to what you're looking for
If you're using WH_KEYBOARD_LL then lparam will hold a KBDLLHOOKSTRUCT in which has a vkcode member you can check against
I can probably write you up a working sample if need be?
if you using WH_KEYBOARD then the wparam in your callback will hold the virtual keycode whicih you can then compare to what you're looking for
If you're using WH_KEYBOARD_LL then lparam will hold a KBDLLHOOKSTRUCT in which has a vkcode member you can check against
I can probably write you up a working sample if need be?
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