C / C++ / MFC

Re: can anybody tell me how to capture the enter key event from the keyboard

30-Oct-07 21:39

See PreTranslateMessage also you can use of WM_KEYDOWN/UP.

Rajesh R Subramanian30-Oct-07 22:04

Rajesh R Subramanian

30-Oct-07 22:04

See here[^].

Real men drive manual transmission

Re: can anybody tell me how to capture the enter key event from the keyboard

Nelek30-Oct-07 22:29

Nelek

30-Oct-07 22:29

Use the WM_KEYDOWN / WM_KEYUP and compare the parameter/variable nChar (contains info about which one was pressed).

Then compare it with an if if you just want to check once, or a switch if you want to differenciate more cases. Some possibilities are: VK_HOME, VK_END, VK_UP, VK_DOWN, ..., VK_PRIOR, ..., VK_ESCAPE, VK_ENTER... and so on, the complete list is in your docu and in MSDN.

Greetings.

--------
M.D.V.

If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?

Help me to understand what I'm saying, and I'll explain it better to you

Wink | ;)

Re: can anybody tell me how to capture the enter key event from the keyboard

Hamid_RT30-Oct-07 22:51

Re: can anybody tell me how to capture the enter key event from the keyboard

30-Oct-07 22:51

Of course if you have a control on the form then all focus send to that control.

philiptabraham30-Oct-07 23:19

philiptabraham

30-Oct-07 23:19

i tried like this
if(::GetKeystate(VK_ENTER<0)
{
mESSAGE
}
ELSE
{
MESSAGE
}

it is showing that vk_enter is undeclared where as it was working properly with vk_control,vk_shift etc

Re: can anybody tell me how to capture the enter key event from the keyboard

Nelek7-Nov-07 3:32

Nelek

7-Nov-07 3:32

sorry, but I don't know what is happening. I have checked the docu to know if I told you a bad name, but it is VK_ENTER. So... if not working with it... I can not tell you what is wrong with it.

BTW, should not be another ) in your code?

if(::GetKeystate(VK_ENTER)<0)

How to close the Opened process.

GauranG Shah30-Oct-07 21:12

GauranG Shah

30-Oct-07 21:12

I am using following code to create the new process. Now I want to Close the process that I have created. I am using CloseHandle() to close the Process with process handle as argument. But its not working.

The following code Opens the MSPAINT success fully when I press the 'c' But it doesn't get closed when I press the 't'.

PROCESS_INFORMATION OpenProc( TCHAR *CmdLine)
{
	TCHAR str[100]	={};
	_tcscpy_s( str, 100, CmdLine );

	STARTUPINFO si;
	PROCESS_INFORMATION pi;

	BOOL ProcCreated;
	ZeroMemory(&si,sizeof(si));
	si.cb			= sizeof(si);
	si.dwFlags		= STARTF_USESHOWWINDOW;
	si.wShowWindow	= SW_SHOWMAXIMIZED;
	ZeroMemory(&pi,sizeof(pi));

	//si.lpDesktop	= _T("NewDesktop");
	si.lpDesktop	=	NULL;
	ProcCreated =CreateProcess( NULL,str,NULL,NULL,FALSE,0,NULL,NULL,&si,&pi );          

	return pi;

}

int _tmain(int argc, _TCHAR* argv[])
{	
	char ch;
        PROCESS_INFORMATION pi;
	DWORD dError;.
      do 
	{	
		scanf("%c",&ch);
		if(ch == 'c')
			pi=OpenProc(L"MSPAINT");
		if(ch == 't')
		{
		CloseHandle(pi.hProcess);
                dError = GetLastError();   //Error = 0
		CloseHandle(pi.hThread);
		dError = GetLastError();  //dError =0
		}

	} while(ch != 'E');
 }

[ Screen Capture ][ Tool Tip ]

Hamid_RT30-Oct-07 22:08

30-Oct-07 22:08

Why you dont use of TerminateProcess?

GauranG Shah30-Oct-07 23:05

GauranG Shah

30-Oct-07 23:05

I used the Code Like this to terminate the process.
The code works fine when the Created Process is in the same desktop. But It doesnn't success when the Process created is in another Desktop.It doesn't show any Error but it doesn't close the opened process.

//dwExitCode = 259 Always. if process is in another Desktop 
GetExitCodeProcess(pi.hProcess,&dwExitCode); 
TerminateProcess(pi.hProcess,dwExitCode);

[ Screen Capture ][ Tool Tip ]

Hamid_RT31-Oct-07 4:32

31-Oct-07 4:32

Can you get handle to this window and then send WM_CLOSE to it?

Nishad S30-Oct-07 22:53

Nishad S

30-Oct-07 22:53

MSDN clearly says that "Closing a thread handle does not terminate the associated thread"

- NS -

David Crow31-Oct-07 3:14

David Crow

31-Oct-07 3:14

GauranG33 wrote:
TCHAR str[100] ={};
...
DWORD dError;.

These two statements are in error. That has no bearing on your problem, however, but it does make it somewhat difficult to debug something with syntax errors.

"Normal is getting dressed in clothes that you buy for work and driving through traffic in a car that you are still paying for, in order to get to the job you need to pay for the clothes and the car and the house you leave vacant all day so you can afford to live in it." - Ellen Goodman

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

JudyL_MD31-Oct-07 3:52

JudyL_MD

31-Oct-07 3:52

Send the opened process a WM_CLOSE message. Just closing your handle to it does not close the process.

You've received some suggestions to use TerminateProcess - that is the last way you should try if you can't close a process nicely. Using TP can causes memory leaks and issues if the process is using any kind of inter-process communication. It is a function-of-last-resort.

Judy

Problem in CRecordSet

M_Menon30-Oct-07 21:08

30-Oct-07 21:08

Hi friends

I am really new with Visual C++. I am using MS Access for DB.
I am trying to take data from a table and pass it to my recordset rs.
I am trying to check if i have received any records for my statement.

my code is

rs is CRecordSet.

While(!rs.IsEof)
{}

Here even when my DB has returned no data it goes inside the While statement.
I believe this is the standard statement to check if you DB has returned zero rows or no data, or whatsoever.

But even when i get Data or i dont still it executes statements inside While.

Any help would be appreciated.

Thanks

Cheers

Menon

panthal30-Oct-07 21:30

panthal

30-Oct-07 21:30

use this code ,

while(!recset.IsEOF()) // Do until EOF
{
}

M_Menon30-Oct-07 22:57

30-Oct-07 22:57

hi there

I am using
while(rs.IsEOF())
{}

but still...it goes inside the while loop.
thanks

Cheers

Menon

David Crow31-Oct-07 3:40

David Crow

31-Oct-07 3:40

mady1380 wrote:
while(rs.IsEOF())
{}

but still...it goes inside the while loop.

Because rs.IsEOF() is evaluating to true, thus the while loop is executing.

Why don't you copy/paste the exact code you are using rather than mangle it all up by retyping it?

M_Menon31-Oct-07 5:45

31-Oct-07 5:45

Hi Friends i am Sorry for not writing the complete code.

Here is my code

CRecordset rs( &db );
tmp.Format( _T("SELECT MAX(Polhsh_ID) FROM Polhsh WHERE Installation_ID = %d"), Installation_ID);
db.ExecuteSQL( tmp );
rs.Open( CRecordset::forwardOnly, tmp, CRecordset::readOnly );
while( !rs.IsEOF())
{
CDBVariant ID;
rs.GetFieldValue( (short)0, ID );
m_Polhsh_ID= ID.m_lVal;

Now my problem is even though my Table Polhsh is empty and has no records, it is going inside the while loop. And henceforth i get an error as the line
rs.GetFieldValue( (short)0, ID );

Thanks

Cheers

Menon

David Crow31-Oct-07 5:52

David Crow

31-Oct-07 5:52

mady1380 wrote:
db.ExecuteSQL( tmp );

This statement is not necessary.

mady1380 wrote:
Now my problem is even though my Table Polhsh is empty and has no records...

How are you verifying this?

mady1380 wrote:
And henceforth i get an error as the line
rs.GetFieldValue( (short)0, ID );

What error?

M_Menon31-Oct-07 7:09