C / C++ / MFC

14-May-07 22:49

Ok, I'm new to doing this in C++, although I have done it in C#. As this code has to work inside another larger C++ project I have (game program) I can't just do it in C#.

In my click handler for a button I want to put text into a textbox control on my form. Unfortunately, the "text" is in a c-string (ie null terminated string), and so I'm not sure how to get it to work:

System::Void btnGen_Click(System::Object^ sender, System::EventArgs^ e)
{
BYTE bMacaddress[MAC_DIM];
CSoftwareKey::RetrieveMACAddress(bMacaddress);

char* pMacString = NULL;
CSoftwareKey::Buffer2HexString( bMacaddress, MAC_DIM, &pMacString );

tbMacAddress->Text = *pMacString; // <---- Problem line
}

I tried first making a string:

string strMacAddr(pMacString);

and then:

tbMacAddress->Text = pMacString;

but this doesn't work either (and I'm sure you are laughing now) =)

Anyway, how can I do this? Basically, pMacString points to something like this:

"000C41805D2D\0" ( if I am making sense )

and so that's what I want in the text box.

Thanks

Patrick

Nelek14-May-07 23:34

14-May-07 23:34

Mmmm,

are you asking to port from c# to c++? or c++ to c#?

Because... there are elements in your code that are unknown for me :S

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?

Stick^14-May-07 23:40

14-May-07 23:40

No, the above code has nothing to do with C#, it is straight C++.

Nelek15-May-07 1:01

15-May-07 1:01

then I'm more newbie than I thought D'Oh! | :doh:

:P

hehehehe

I've never seen "^" used as "System::Object^ sender"

Nevermind,

your tbMacAddress->Text is a string or a char[x]?

I had some problems with CString and char* in VC++ because of the "\0" at the end of the CStrings. I solved it considering the CString as a vector and taking every letter in a loop and putting it in the place of the char[20] that was needed. Afterwards I passed the &char[0] where the LPCSTR was asked for and it worked. Finally I found another way to do it and changed it but... sometimes silly things give the way to the correct answer.

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?

Hamid_RT15-May-07 0:56

15-May-07 0:56

Your code is managed it was better you asked on the (Managed) C++/CLI[^]

WhiteSky

Stick^15-May-07 1:10

15-May-07 1:10

My question has nothing to do with managed code.

Basically, forget the code which is confusing you, and just think of this as the question:

If you have a c-string (ie a null terminated string) and you want to set the Text in a textbox to that value, how do you do it?

For example, when a button on the form is pushed, set the textbox to the c-string's value.

Patrick

Nelek15-May-07 1:44

15-May-07 1:44

Hi,

to do that I associate a member variable (CString) to the CEditBox and when I push a button or happens whatever it shall happen, call UpdateData (FALSE);

On the other hand, as the CEdit is derived from CWnd. It should be possible to modify its text with SetWindowText( LPCTSTR lpszString ); but I'm not sure because I have never tried it, I do it as above (VC++ 6)

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?

Stick^15-May-07 2:21

15-May-07 2:21

Code?

So if I tell you that you are given a variable:

myString[] = "0C34AZ"; // which is null terminated

what would be working code to put it in a textbox?

Nelek15-May-07 3:12

15-May-07 3:12

Hi another time,

ok, I have the DoDataExchange in my Form, and a member variable associated to my CEdit.
DDX_Text(pDX, IDC_MYEDIT, m_szMemberString);

I initialize it to “” (empty) in the constructor.

And then, in some events/messages I put the name of another element I saved in the Document, in the example a click in a ListCtrl (report mode) where my elements are listed

void CMyFormView::OnClickCtrlList(NMHDR* pNMHDR, LRESULT* pResult) 
{	POSITION pos = m_clcMyList.GetFirstSelectedItemPosition();

	//If the click was outside the range
if (!pos)
	{	m_nRowNum = -1;
		m_cbButton1.EnableWindow (FALSE);
		m_ szMemberString = "";
		UpdateData (FALSE);
	}
	
	while (pos)
	{	m_nRowNum = m_clcRuleList.GetNextSelectedItem(pos);
		M_szMemberString = pDoc->GetElementNameOfColumn (m_nRowNum);
		m_cbButton1.EnableWindow (TRUE);
		UpdateData (FALSE);
	}

	Invalidate ();			UpdateWindow ();
	*pResult = 0;
	return;
}

Another way (without member variables and the DoDataExchange) can be:

void CMyFormView::OnClickCtrlList(NMHDR* pNMHDR, LRESULT* pResult) 
{	POSITION pos = m_clcMyList.GetFirstSelectedItemPosition();
	CEdit* pEdit = (CEdit*)GetDlgItem (IDC_MYEDIT);

	//If the click was outside the range
	if (!pos)
	{	m_nRowNum = -1;
		m_cbButton1.EnableWindow (FALSE);
		pEdit->SetWindowText ("");
	}
	
	while (pos)
	{	m_nRowNum = m_clcRuleList.GetNextSelectedItem(pos);
		pEdit->SetWindowText (pDoc->GetElementNameOfColumn (m_nRowNum));
		m_cbButton1.EnableWindow (TRUE);
	}

	Invalidate ();			UpdateWindow ();
	*pResult = 0;
	return;
}

The function I’m using is: CString CMyDoc::GetElementNameOfColumn (int nRow);

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?

Stick^15-May-07 3:21

15-May-07 3:21

I just realised why I'm having the problem I'm having.

I started a straight C++ project, and added a CLR form! I really didn't want a managed form, as I want to stick with unmanaged C++. duh

So, basically, either I do this in C# ( or managed C++ ) or I have to learn how to do windows forms Frown | :(

I think I'll stick to a console app to do this simple job and avoid the whole dang problem.

Windows programming is just to much of a pain to learn.

Nelek15-May-07 21:11

15-May-07 21:11

Hehehehe,

This is the same my partner said. He try to piss me off with "look, in VB I can print with just 2 lines", because I'm having problems to personalize a PrintDialog, margins, Bitmaps...

Windows programming is not easy at all. But it is not imposible, just a question of time and being persistent.

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?

Hamid_RT15-May-07 1:53

Changing datatype from VB.NET to VC++ 6.0

15-May-07 1:53

If you want to set text for a control Textbox(editbox) or button you can use of SetWindowText();

WhiteSky

ctlqt1214-May-07 22:36

ctlqt12

14-May-07 22:36

Hi all,

I have created a dll file in VC++ 6 and use that dll file in VB.Net. But unfortunately, in VC++, I'm using some datatype that aren't supported in VB.Net. So i couldn't use that dll file.

Please show me what datatype i should use in VB.NET appropriate with following datatype in VC++ 6 :

BSTR -> what datatype in VB.NET i should use
LPCTSTR -> what datatype in VB.NET i should use
LPSTR -> what datatype in VB.NET i should use
unsigned int -> what datatype in VB.NET i should use
DWORD -> what datatype in VB.NET i should use

Please show me some guide. Any help will be welcome.

Best Regards

Re: Changing datatype from VB.NET to VC++ 6.0

fang_eric15-May-07 0:13

fang_eric

15-May-07 0:13

BSTR->string
LPCTSTR->const string
LPSTR -> string
unsigned int->UInt32
DWORD -> long

Registry notification

Alexandre GRANVAUD14-May-07 21:43

Alexandre GRANVAUD

14-May-07 21:43

Hi Cool guys of this messageboards suggested me to use RegNotifyChangeKeyValue() function in order to be informed/notified of registry modifications (what i'm looking at).
It works but it only notifies me that something changed but i can't find how to figure exactly WHAT changed ?

thanks Smile | :)

Re: Registry notification

Rajesh R Subramanian15-May-07 7:16

Rajesh R Subramanian

15-May-07 7:16

RegNotifyChangeKeyValue() will notify you of any changes that is made to the key that *you* pass the API as the first parameter, hKey.

Alexandre GRANVAUD wrote:
It works but it only notifies me that something changed but i can't find how to figure exactly WHAT changed ?

Use RegQueryValueEx() to get the modified value of the registry key. You could compare it to the old value, and you'd know what's changed.

Shog on learning VB6: Ah, that would have been VB6. Kicked my ass anyway.
So easy to learn, just like falling down a flight of stairs...

Re: Registry notification

Alexandre GRANVAUD15-May-07 7:22

Alexandre GRANVAUD

15-May-07 7:22

yes but i need to know which subkeys are created in a large tree

How to print with a new CPrintDialog derived DBox??

Nelek14-May-07 21:03

Re: How to print with a new CPrintDialog derived DBox??

14-May-07 21:03

Hi all,

I have a little problem with printing. The case is that my program has multiple views and I need to print different things depending of the view that is active in this moment. I have derived a Dialog from CPrintDialog to allow some parameters selection and to print different outputs according to these parameters. I have successfully called the new DialogBox and set the parameters to choose the output. My problem is that, as I have overridden the CNewPrintDialog::OnOk () to modify the things I need, when I click OK in my dialog and send the work to print… I have an error because the DeviceContext for the printer is not correctly saved in pInfo->m_pPD->m_pd.m_hDC. My question is… where can I find the implementation (not the definition) of the CPrintDialog to see its CPrintDialog::OnOk and copy what I need in my Dialog??? Confused | :confused:

Or… How should I make it to successfully send the datas to be printed? I have tried to print with what Chris Maunder’s says in one of his articles (Printing without the Document/View framework) but it doesn’t solves my problem because I do use the framework Cry | :((

Any help will be wellcome

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?

Hamid_RT14-May-07 22:01

Re: How to print with a new CPrintDialog derived DBox??

14-May-07 22:01

Nelek wrote:
an error because the DeviceContext for the printer is not correctly saved in pInfo->m_pPD->m_pd.m_hDC

Can you show how do you set m_hDC and see Print Bitmaps without Doc/View Framework[^] is helpfuls?

WhiteSky

Nelek14-May-07 22:50

Re: How to print with a new CPrintDialog derived DBox??

14-May-07 22:50

Hi,

I have made:

BOOL CMyView::OnPreparePrinting(CPrintInfo* pInfo)
{
CMyDoc* pDoc = GetDocument ();
ASSERT_VALID (pDoc);
delete pInfo->m_pPD ; // release previous MFC allocated dialog object
pInfo->m_pPD = new CDlgPrinting(FALSE, PD_ALLPAGES | PD_USEDEVMODECOPIES | PD_NOPAGENUMS | PD_HIDEPRINTTOFILE | PD_NOSELECTION, this) ;
pInfo->m_pPD->m_pd.hInstance = AfxGetInstanceHandle();
pInfo->m_pPD->m_pd.lpPrintTemplateName = MAKEINTRESOURCE(IDD_PRINT_PRDLG);
pInfo->m_pPD->m_pd.Flags |= PD_ENABLEPRINTTEMPLATE;
pInfo->m_pPD->m_pd.nMinPage = 1;

pInfo->SetMaxPage (CalculateNumberOfPages ());

//BOOL bAnswer = DoPreparePrinting(pInfo);
int nAnswer = pInfo->m_pPD->DoModal ();
if (nAnswer == IDCANCEL)
	return FALSE;

CDC dc;
dc.Attach (pInfo->m_pPD->GetPrinterDC ());
pInfo->m_pPD->m_pd.m_hDC = dc.GetSafeHdc ();

if (m_byPrintParam)
	AfxMessageBox ("Parameters modified");
	//Here it will be made the selection of what has to be printed
else
	MessageBox (NULL, "Error by taking parameters", "Error", MB_OK);

dc.Detach ();  //Edited: I forgot this line
return TRUE;
}

But I get an Assertion and he brings me to code
ASSERT (pInfo->m_pPD->m_pd.m_hDC != NULL);

EDIT

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?

Hamid_RT15-May-07 5:59