C / C++ / MFC

11-Feb-09 22:43

Hi,
i'm new to c preprocessor and i would like to do some string replacement in a text file using c preprocessor.

the code is something like this
---
#define __TOREPLACE__ replaced

path/subpath/__TOREPLACE__

path\__TOREPLACE__image.png
---

the output is:
...
path/subpath/replaced

path\__TOREPLACE__image.png
...

as seen, there is a replacement in the first path, but not in the second one.
why isn't the second one replaced ?

is this a good approach at all ?

thanks in advance

Iain Clarke, Warrior Programmer

Iain Clarke, Warrior Programmer11-Feb-09 22:52

11-Feb-09 22:52

Just a guess... But try it with a double \\. In C files, a single \ means the next character has something special about it. Well, it quoted strings it does!

And as your paths aren't valid commands or variable names, I'm guessing you left out the rest of the line and the quotation marks?

Iain.

Codeproject MVP for C++, I can't believe it's for my lounge posts...

tarcairion11-Feb-09 23:04

11-Feb-09 23:04

thanks for your answer, Iain.

i've already tried using the double backslash, but no real effect.

the code i've posted is only seen as an example.
the text files i would like to be preprocessed are no real c code,
more like text conf files, where some text variables have to be replaced.

Stuart Dootson11-Feb-09 23:28

Stuart Dootson

11-Feb-09 23:28

I've already given you an answer - but with this extra information...I'd suggest you might be better off using something other than the C pre-processor. awk, m4, perl? They're all available using something like gnuwin32[^].

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

Naveen11-Feb-09 23:10

11-Feb-09 23:10

I guess the macro should be modified as follows

#define __TOREPLACE__ "replaced"

and used like

"path/subpath/"__TOREPLACE__

"path\"__TOREPLACE__"image.png"

tarcairion11-Feb-09 23:34

11-Feb-09 23:34

thanks Naveen, but unfortunately,
the result is not what i wanted.

"path/subpath/""replaced"

"path\"__TOREPLACE__"image.png"

Naveen11-Feb-09 23:41

11-Feb-09 23:41

tarcairion wrote:
"path\"__TOREPLACE__"image.png"

you should put double slashes...

"path\\"__TOREPLACE__"image.png"

Stuart Dootson11-Feb-09 23:13

Stuart Dootson

11-Feb-09 23:13

The C pre-processor is seeing __TOREPLACE__image.png as a single identifier. That identifier isn't __TOREPLACE__, so it doesn't replace it.

If you want to 'glue' a replaced value to some static text, you'll need something like this:

#define GLUE2(A, B) A##B
#define GLUE(A, B) GLUE2(A,B)

#define __TOREPLACE__ replaced

path/subpath/__TOREPLACE__

GLUE(path\,GLUE(__TOREPLACE__,image.png))

That works OK under the VC++ pre-processor, giving this output:

path/subpath/replaced

path\replacedimage.png

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

tarcairion11-Feb-09 23:37

How to call SQL Server Stored procedure from C++ code

11-Feb-09 23:37

thank you for your answer, Stuart. this works, indeed.
i seems to be that the preprocessor has some difficulty
to identify a #define in some places due to missing
delimiters
but as you stated it may not be the best approach, so
i will try something else like you mentioned.

PankajB11-Feb-09 22:42

PankajB

11-Feb-09 22:42

Hi there.

We have some stored procedures on a remote SQL Server.

Now, from my local machine using C++ I want to call a stored procedure.
Please provide sample code if available for the same.

Incase any further information required, please let me know.

Thanks and Regards
PanB

Re: How to call SQL Server Stored procedure from C++ code

CPallini11-Feb-09 23:48

CPallini

11-Feb-09 23:48

Let's me try to use Google for you...^
Smile | :)

problem of creating a dialogbox

VCProgrammer11-Feb-09 22:31

VCProgrammer

11-Feb-09 22:31

Hi all,

I have made a dialog based application in vc-2008. I have made 2 more dialog boxes...

Now what i have to do is on button click event 1st dialog box is called, so first dialog box OnInitDialog function is being called in that function second dialog box DoModal function has been called... Now what i want is if second dialog box return 1 i.e its successful then only first dialog box should be constructed and do its processing otherwise it should not be constructed.....

for example

CFirstDialog dlg;
dlg.DoModal();

BOOL CFirstDialog::OnInitDialog() 
{
CSecondDialog dlg1;
int ret_val = dlg1.DoModal();

if(ret_val == 1)
return true;//i.e dialogbox should be created
else
return false;// dialog should not be created
}

but this code is not solving my problem...

its giving me a dialog box(first) in not working condition....

how to do this....

can anybody help me in this...

thanks in advance

Re: problem of creating a dialogbox

Cedric Moonen11-Feb-09 22:37

Cedric Moonen

11-Feb-09 22:37

Why do you want to do that in the OnInitDialog from CFirstDialog ? Can't you simply move the condition check at the place where you create CFirstDialog originally ? There you first create CSecondDialog and if the return condition is not what you expect, then you don't create CFirstDialog. Seems a bit better than putting that in the OnInitDialog...

Cédric Moonen
Software developer

Charting control [v1.5]
OpenGL game tutorial in C++

Re: problem of creating a dialogbox [modified]

Iain Clarke, Warrior Programmer11-Feb-09 22:57

Iain Clarke, Warrior Programmer

11-Feb-09 22:57

Cedric's answer is good - you're testing too late. Why go to all the bother of making a dialog then throwing it away?

Saying that, you may have a very good reason.

So...

As you're a VCProgrammer, you should be familiar with documentation. OnInitDialog / WM_INITDIALOG has some too. Here's an extract:

Return Values
The dialog box procedure should return TRUE to direct the system to set the keyboard focus to the control specified by wParam. Otherwise, it should return FALSE to prevent the system from setting the default keyboard focus.

You don't get to make up the meaning of returns values for messages you didn't invent. Otherwise windows programming would be a whole lot more... interesting...

I'm pretty sure you can call EndDialog from within OnInitDialog though, which would give you a hacky answer - but Cedric's solution would be a lot cleaner.

Iain.

Codeproject MVP for C++, I can't believe it's for my lounge posts...

modified on Thursday, February 12, 2009 5:05 AM

Re: problem of creating a dialogbox

aks.11-Feb-09 23:08

aks.

11-Feb-09 23:08

just call EndDialog() instead of return false;// dialog should not be created

aks

Scrolling in List box

m_mun11-Feb-09 22:30

m_mun

11-Feb-09 22:30

Hi All,
I have used a List box control. But i cant show the automatic scroll down when something added in the list box. I cannot see which item added recent. If i want to see i have to scroll down by mouse.

Thanks to all

Regards
Munna

Re: Scrolling in List box

Naveen11-Feb-09 22:46

11-Feb-09 22:46

Use the CListBox::SetTopIndex()[^] function. Pass the index of newly add item to this function to bring that item to visible.

Re: Scrolling in List box

Code-o-mat12-Feb-09 5:44

Code-o-mat

12-Feb-09 5:44

Additionally to what Naveen said, there is also CListCtrl::EnsureVisible[^].

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Life: great graphics, but the gameplay sux. <

How to know 32 or 64 bit

john563211-Feb-09 22:27

john5632

11-Feb-09 22:27

Hi All,

Is there any API to know about the 32 or 64 bit machine?

Re: How to know 32 or 64 bit

Naveen11-Feb-09 22:49

11-Feb-09 22:49

Check Getting the System Version[^]