Redirect the output - C / C++ / MFC Discussion Boards

JudyL_MD15-Feb-08 9:34

15-Feb-08 9:34

Rajesh R Subramanian wrote:
Mark Salsbery wrote:
Service Control Handler Function[^]

Sounds more like a candidate for the Buzzword hall of shame forum.

Nope

, it's actually a very concise description of the subject at hand - the specifics of the function which handles control messages for a service. MS surprisingly actually titled the page with meaningful text.

Judy

Re: Delay Windows shutdown

RoyceF19-Feb-08 4:36

RoyceF

19-Feb-08 4:36

Thanks everyone for the help. The AbortShutdown() is what I was looking for. I know about the WM_QUERYENDSESSION message and how to handle it. Originally, I was looking for a way to get around the hidden window in my service, but because I have to interact with my user, I must use it.

WH_KEYBOARD_LL

codeinelogic15-Feb-08 3:38

codeinelogic

15-Feb-08 3:38

If anyone can please write a simple function using the low-level keyboard hook WH_KEYBOARD_LL i would greatly appreciate it, although i use boralnd builder 6 instead of visual the concepts are still the same, i would apprciate a function that sets/unsets the hook and just a simple hook declaration, i've read the post/topics about it but i just cant seem to get it to work. help please Sigh | :sigh:

Re: WH_KEYBOARD_LL

Rajesh R Subramanian15-Feb-08 3:56

Rajesh R Subramanian

15-Feb-08 3:56

There's an article here[^] which demonstrates the same. Smile | :)

Nobody can give you wiser advice than yourself. - Cicero
.·´¯`·->Rajesh<-·´¯`·.
Codeproject.com: Visual C++ MVP

Re: WH_KEYBOARD_LL

David Crow15-Feb-08 4:10

David Crow

15-Feb-08 4:10

codinelogic wrote:
i've read the post/topics about it but i just cant seem to get it to work.

Show us what you've tried.

"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

Re: WH_KEYBOARD_LL

codeinelogic16-Feb-08 5:50

codeinelogic

16-Feb-08 5:50

defines and includes included [hehe]

<br />
#define WIN32_LEAN_AND_MEAN<br />
<br />
#define STRICT<br />
<br />
#include <windows.h><br />
<br />
HHOOK hKeyboardHook;<br />
HINSTANCE hInst;

and than the hook along with the on off function..

LRESULT CALLBACK LowLevelKeyboardProc(int nCode, WPARAM wParam, LPARAM lParam) <br />
{<br />
    PKBDLLHOOKSTRUCT k;<br />
<br />
    if (nCode == HC_ACTION) <br />
    {<br />
        k = (PKBDLLHOOKSTRUCT) lParam;<br />
<br />
        if (

here is where i will choose to disable keys

return 1;<br />
   }<br />
                    <br />
   return CallNextHookEx(hKeyboardHook, nCode, wParam, lParam);<br />
}

the turn on...

hKeyboardHook  = SetWindowsHookEx(WH_KEYBOARD_LL,<br />
                                  LowLevelKeyboardProc,<br />
                                  hInst,<br />
                                  0);

the turn off..

UnhookWindowsHookEx(hKeyboardHook);<br />
hKeyboardHook = NULL;<br />

a note: without define strict i receive an error in the lpfn parameter.
also it will compile without win23_lean_and_mean but while reading
other's articles it seemed recomended.

Re: WH_KEYBOARD_LL

David Crow18-Feb-08 2:32

David Crow

18-Feb-08 2:32

If you are receiving a compiler error, what is it, and what line is it on?

Redirect the output

bhat15-Feb-08 3:28

bhat

15-Feb-08 3:28

Editor VS6
Language:VC++

my task is to run the DOS cmd from my application (ie on button click)and redirect the output in my applications Edit box without showing the console window

how to do it ...........
Code is preffered

AbidBhat

Re: Redirect the output

led mike15-Feb-08 4:08

led mike

15-Feb-08 4:08

abid wrote:
Code is preffered

I bet, but around here we prefer people write their own code. Read the first post in forum titled "How to get an answer to your question".

led mike

Re: Redirect the output

David Crow15-Feb-08 4:09

David Crow

15-Feb-08 4:09

abid wrote:
how to do it ...........

See here and here.

How to assign/ map Left arrow key to a specific character suppose letter 'L'

Abhijit D. Babar15-Feb-08 2:38

Abhijit D. Babar

15-Feb-08 2:38

I have problem in SDK/ MFC.
I have to assign/map 'Down' or 'Up' arrow key to a specific character suppose letter 'D' or 'U' or any other character. So that when i press 'D' or 'U', it acts or function like a Up or Down arrow key..
How can i do this, please help me.

Thanks in advance..

Re: How to assign/ map Left arrow key to a specific character suppose letter 'L'

Rajesh R Subramanian15-Feb-08 2:51

Rajesh R Subramanian

15-Feb-08 2:51

You want such functionality within your application or system-wide? If it is just your application, overriding PreTranslateMessage() may help you.

Nobody can give you wiser advice than yourself. - Cicero
.·´¯`·->Rajesh<-·´¯`·.
Codeproject.com: Visual C++ MVP

Re: How to assign/ map Left arrow key to a specific character suppose letter 'L'

Maximilien15-Feb-08 2:57

Maximilien

15-Feb-08 2:57

Handle the 'D' or 'U' and call the same code that you call when handling the 'up' or 'down' keys.

Maximilien Lincourt
Your Head A Splode - Strong Bad

Re: How to assign/ map Left arrow key to a specific character suppose letter 'L'

Rajesh R Subramanian15-Feb-08 3:42

Rajesh R Subramanian

15-Feb-08 3:42

Maximilien wrote:
call the same code that you call when handling the 'up' or 'down' keys.

He may not have any code to be called while the up or down arrow keys are pressed. I understand that his requirement was to just simulate an up arrow key press while 'U' is pressed and down arrow key press if 'D' is pressed.

Also, how do you handle 'D' or 'U'? Say, if there are multiple child controls in the application window, those child controls may be having the keyboard focus!

Nobody can give you wiser advice than yourself. - Cicero
.·´¯`·->Rajesh<-·´¯`·.
Codeproject.com: Visual C++ MVP

Background color of CToolBar. [modified]

Paresh Chitte15-Feb-08 1:24

Paresh Chitte

15-Feb-08 1:24

Hi,

How can I change the background color of CToolBar ?

Regards,
Paresh.

modified on Monday, February 18, 2008 1:17 AM

Recycle Bin Files and Folders

john563214-Feb-08 23:30

john5632

14-Feb-08 23:30

I'm writing my first shell extension dll, and I'm trying to figure out how to pass the Recycle bin files/folders anme CShellExt::InvokeCommand at right click of menu item. I am getting others files and folders name.
Some sennipt is attached.

<br />
void CCoMenHandler::GetSelectedFiles(LPCITEMIDLIST pidlFolder,IDataObject *pdtobj)<br />
{<br />
// get these paths into a CStringArray<br />
g_szSelectedFiles.RemoveAll();<br />
<br />
// fetch all of the file names we're supposed to operate on<br />
if (pdtobj) <br />
{<br />
pdtobj-&gt;AddRef();<br />
<br />
STGMEDIUM medium;<br />
FORMATETC fe = { CF_HDROP, NULL, DVASPECT_CONTENT, -1, TYMED_HGLOBAL};<br />
<br />
<br />
HRESULT hr = pdtobj-&gt;GetData (&amp;fe, &amp;medium);<br />
if (FAILED (hr))<br />
{<br />
return ;<br />
}<br />
<br />
// buffer to receive filenames<br />
char path[MAX_PATH];<br />
<br />
// how many are there?<br />
UINT fileCount = DragQueryFile((HDROP)medium.hGlobal, 0xFFFFFFFF,<br />
path, MAX_PATH);<br />
<br />
if (fileCount&gt;0)<br />
{<br />
// avoid wasting mem when this thing gets filled in<br />
g_szSelectedFiles.SetSize(fileCount);<br />
<br />
// stash the paths in our CStringArray<br />
for (UINT i=0;i&lt;fileCount;i++) <br />
{<br />
// clear old path<br />
memset(path, 0, MAX_PATH);<br />
// fetch new path<br />
if (DragQueryFile((HDROP)medium.hGlobal, i, path, MAX_PATH)) <br />
{<br />
g_szSelectedFiles.SetAt(i, path);<br />
//AfxMessageBox(path);<br />
}<br />
}<br />
<br />
g_szSelectedFiles.FreeExtra();<br />
}<br />
<br />
// free our path memory - we have the info in our CStringArray<br />
ReleaseStgMedium(&amp;medium);<br />
}<br />
<br />
<br />
}<br />

Thanx in advance.:

my code breaks unique pointer rule?

George_George14-Feb-08 23:06

George_George

14-Feb-08 23:06

Hello everyone,

Unique pointer should not allow aliasing. But my code which contains unique pointer aliasing and also compile/run ok. Anything wrong?

__interface IFoo {

public:

	virtual int foo ([unique] char  *ptr1, [unique] char  *ptr2) = 0;
};

class Foo : public IFoo {

public:

	int foo (char  *ptr1, char  *ptr2)
	{
		char array1[] = "Hello";

		ptr1 = array1;
		ptr2 = array1; // should be wrong, no aliasing allowed, but compile and run ok
		
		return 0;
	}
};


int main()
{
	char* ptr1 = 0;
	char* ptr2 = 0;

	Foo f;
	f.foo(ptr1, ptr2);

	return 0;
}

thanks in advance,
George

Error while exporting a static member form a DLL

Prasanth M V14-Feb-08 23:04

Prasanth M V

14-Feb-08 23:04

Hi Friends,

I want to export a class and its static member from the DLL.
I could build the DLL.
And i want to use that exported class and its static members form that Dll in my C++ application. But when i am building application i am getting a link error for that static member.

error LNK2001: unresolved external symbol "public: static int CMyClass::i" (?i@CMyClass@@2HA).

The IDE that i am using is Visual Studio 6.0.

Plz help me Wink | ;)

The details of the implementation is as follows...

//////////////////////DLL PART//////////////////////////

// MyClass.h: interface for the CMyClass class.
//---------------------------------------------

#define _MYDLL

#ifdef _MYDLL
#define MY_API __declspec(dllexport)
#else
#define MY_API __declspec(dllimport)
#endif

class MY_API CMyClass
{
public:
CMyClass();
virtual ~CMyClass();

public:
static int i;

};

// MyClass.cpp: implementation of the CMyClass class.
//-------------------------------------------------
#include "stdafx.h"
#include "MyClass.h"

int CMyClass::i;

CMyClass::CMyClass()
{

}

CMyClass::~CMyClass()
{

}

//////////////////////////////CALLING APPLICATION//////////////////////////

In my application i try to use that static member as below;

#include "MyClass.h"
_tmain()
{

int nValue = CMyClass::i; Smile | :)

}

Re: Error while exporting a static member form a DLL

CPallini14-Feb-08 23:23

CPallini

14-Feb-08 23:23

See here [^]
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

Re: Error while exporting a static member form a DLL

Prasanth M V17-Feb-08 22:15

Prasanth M V

17-Feb-08 22:15

Hi,
I corrected the code as follows.
And i defined _MYIF in the project settings.
The Dll could build successfully.

But when i ma using this in amy application , it is showing an error
error LNK2001: unresolved external symbol "public: static int CMyClass::nValue" (?nValue@CMyClass@@2HA)

Plase see the classs impelmentation as follows.

Does any have any idea?????

//MyClass.h

#ifdef _MYIF
#define MY_API __declspec(dllexport)
#else
#define MY_API __declspec(dllimport)
#endif

class MY_API CMyClass
{
public:
CMyClass();
virtual ~CMyClass();

public:
static int nValue;

};

//MyClass.cpp
#include "MyClass.h"

int CMyClass::nValue = 0;

CMyClass::CMyClass()
{

}

CMyClass::~CMyClass()
{

}

Re: Error while exporting a static member form a DLL

CPallini17-Feb-08 22:35

CPallini

17-Feb-08 22:35

Prasanth M V wrote:
But when i ma using this in amy application , it is showing an error
error LNK2001: unresolved external symbol "public: static int CMyClass::nValue" (?nValue@CMyClass@@2HA)

You need to link the importation library of the DLL (for instance if your DLL is MyClass.DLL, then you have to link your application with MyClass.lib).
You may add MyClass.lib to the linker command line in the project settings.
Probably you need also to specify the folder wherein the linker may find the importation library (choose Tools->Options menu item then select the Project and Solutions->VC++ Directories, select Library files into the show directories for listbox and finally add the MyClass.lib folder path to the list).

Smile | :)

Re: Error while exporting a static member form a DLL

Prasanth M V17-Feb-08 23:01

Prasanth M V

17-Feb-08 23:01

Hi,

I have already given the import lib file to the project.
And i could access all the class members expect the Static member of the class.
Then ???

Thanks,
Prasanth

Re: Error while exporting a static member form a DLL

CPallini18-Feb-08 0:53

CPallini

18-Feb-08 0:53

Prasanth M V wrote:
I have already given the import lib file to the project.
And i could access all the class members expect the Static member of the class.
Then ???

Then I dont know. I mean, the following very simple test:

DLL header file

#ifdef CPPDLL_EXPORTS
#define CPPDLL_API __declspec(dllexport)
#else
#define CPPDLL_API __declspec(dllimport)
#endif

// This class is exported from the CppDll.dll
class CPPDLL_API CCppDll {
public:
	CCppDll(void);
	~CCppDll(void);
	// TODO: add your methods here.

	static int nValue;
};

DLL source file

// DLLMain stuff
// ...
CCppDll::CCppDll()
{
	return;
}
CCppDll::~CCppDll()
{
	return;
}
int CCppDll::nValue = 0;

client application

#include "stdafx.h"
#include "..\\..\\CppDLL\\CppDLL\CppDLL.h"

int _tmain(int argc, _TCHAR* argv[])
{
	CCppDll::nValue =5;
}

it's working fine on my system.
Smile | :)

Re: Error while exporting a static member form a DLL

Prasanth M V19-Feb-08 0:19

Prasanth M V

19-Feb-08 0:19

Hi All,

Its is workign fine
Thanks for your support Smile | :)

----------------------------------------
But one intesting thing i see is that i give the CPPDLL_EXPORTS in the project settings.

If i am giving it in StdAfx.h i will work.

OK NAy i worked.

Thanks
Alot Smile | :)

Re: Error while exporting a static member form a DLL

Prasanth M V19-Feb-08 0:19

Prasanth M V

19-Feb-08 0:19

Hi All,

Its is workign fine
Thanks for your support Smile | :)

----------------------------------------
But one intesting thing i see is that i give the CPPDLL_EXPORTS in the project settings.

If i am giving it in StdAfx.h i will work.

OK Anyway it worked.

Thanks
Alot Smile | :)

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