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I am developing an app using C # where i want to read the key strokes continously like two or more Ex Windows + M after that Insert + T so i have hook procedure for that and If i integerate it in my code and I am unable to read the key strokes continously I will give the code for the reference can anyone suggest me some ideads to clear this it will very helpful. TIA
if ((nCode >= 0))
{
KBDLLHOOKSTRUCT pKBDLLHOOKSTRUCT = new KBDLLHOOKSTRUCT();
pKBDLLHOOKSTRUCT = (KBDLLHOOKSTRUCT)Marshal.PtrToStructure(lParam, pKBDLLHOOKSTRUCT.GetType());
if (wParam == (IntPtr)WM_KEYDOWN)
{
if (pKBDLLHOOKSTRUCT.vkCode == (short)Keys.M)
{
bool bKeyDown = (GetAsyncKeyState((int)Keys.LWin) & 0x8000) == 0x8000;
if (bKeyDown)
{
return 1;
}
}
if (pKBDLLHOOKSTRUCT.vkCode == (short)Keys.Tab)
{
bool bKeyDown = (GetAsyncKeyState((int)Keys.Tab) & 0x8000) == 0x8000;
if (bKeyDown)
{
return 1;
}
after that It will read only 1st key combination and it is not reading the 2nd key combination and gettin error at mentioned below:-
attForm.ShowDialog(this); // error as mentioned below
Managed Debugging Assistant 'CallbackOnCollectedDelegate'
Message=Managed Debugging Assistant 'CallbackOnCollectedDelegate' : 'A callback was made on a garbage collected delegate of type 'EYEModelLib!EYE.Model.Utility_Classes.KeyBoardInterface+HookProc::Invoke'. This may cause application crashes, corruption and data loss. When passing delegates to unmanaged code, they must be kept alive by the managed application until it is guaranteed that they will never be called.'
@Dineshkumar.S , based on your description, Could you consider registering the hotkey directly? You could look at the question: Global hotkey in console application
No its is also not working and I need one clarification that we can able to that in a windows forms or not ?
Hook procedure and handle must be static
And the second test has no sense (twice Keys.Tab...)
The second one is Insert + tab key combination
static i will check and let you know and thanks for the suggestion
both of them are static only and still I am unable it run it properly after adding in my project where as the code given by you working perfectly in the prototype model
after adding it to my project this code will not reading the exact key strokes and if a key is down it is showing the key combination what we mentioned is correct
I don't understanbd what you mean...
Hook variables must be global too
And there is twice Keys.Tab in your second test , there is no test on Insert key
if (wParam == (IntPtr)WM_KEYDOWN)
{
if (pKBDLLHOOKSTRUCT.vkCode == (short)Keys.M)
{
bool bKeyDown = (GetAsyncKeyState((int)Keys.LWin) & 0x8000) == 0x8000;
if (bKeyDown)
{
return 1;
}
}
if (pKBDLLHOOKSTRUCT.vkCode == (short)Keys.Tab)
{
bool bKeyDown = (GetAsyncKeyState((int)Keys.Insert) & 0x8000) == 0x8000;
if (bKeyDown)
{
return 1;
}
In this case also it is not reading the key strokes
If I add a Beep ( Console.Beep(8000, 10);) it is generated.
Did you set BP to see if it goes into the code ?
no i didnt set beep
I will check setting it
I meant Break Points...
if (wParam == (IntPtr)WM_KEYDOWN)
{
if (pKBDLLHOOKSTRUCT.vkCode == (short)Keys.M)
{
int key = GetAsyncKeyState((int)Keys.LWin); // key = 0 am geting
bool bKeyDown = (GetAsyncKeyState((int)Keys.LWin) & 0x8000) == 0x8000; // getasynckeystate is prob
if (bKeyDown)
{
return 1;
}
as i mentioned above when i add this code to my application it is not reading the key strokes
have you implemented this key strokes in any of your windows form application development ??
because I heard that this getasynckeystate() will not work with windows application properly and it will go correctly only with quick POC
Of course.
GetAsyncKeyState is a Win32 API, which has always worked in desktop applications.
I call the hook in Form1_Load :
KeyboardLLProcedure = new HookProc(KeyboardLLProc);
hHook = SetWindowsHookEx(WH_KEYBOARD_LL, KeyboardLLProcedure, (IntPtr)0, 0);
with globals :
static int hHook = 0;
HookProc KeyboardLLProcedure;
and
public static int KeyboardLLProc(int nCode, IntPtr wParam, IntPtr lParam)
{
//...
}
But In my case the getasynckeystate(0 function not working properly means the code is not reaching that point and I found that it will not work for desktop applications. so can you help me in that for your reference i will add some forum pics
@Dineshkumar.S , you could try the following code to read the key strokes continously by setting a bool variable.
Here is a code example you could refer to.
private bool t = false;
private void Form1_KeyDown(object sender, KeyEventArgs e)
{
if(e.KeyData== (Keys.Control|Keys.F))
{
t = true;
}
if(e.KeyData==(Keys.Alt|Keys.M)&&t)
{
MessageBox.Show("Test");
}
}
Best Regards,
Jack
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Ok let me try this and let you know