C / C++ / MFC

Re: MFC ‘Visio’ style GUI

25-Feb-04 1:55

Just buy the rogue wave components that do this - www.roguewave.com (used to be stingray).

Murphster25-Feb-04 2:09

Murphster

25-Feb-04 2:09

thanks roel but I was hoping to implement a basic version myself - I would use something like you have surgested but it is not going to be a comercial product so would not warrent me spending that much money on it.

But sill the website you gave me is good for research - thanks again.

Re: MFC ‘Visio’ style GUI

roel_25-Feb-04 3:24

25-Feb-04 3:24

Ok in that case I'd write a custom control myself, either using win32 sdk, mfc or wtl, what you're most comfortable with. That would mean handling all the hit-testing, dragging, selections etc manually. I have once written something similar to what you want to do, using different windows for the 'items' in the view but that wasn't the right way to do it. I started redoing it by drawing directly on the custom control but I never finished that (we bought the roguewave thing).

Error while using fopen

torrud25-Feb-04 1:01

25-Feb-04 1:01

Hi,

I'm trying to write a .NET-dll with Visual C++. Always I want to use fopen I get this error:

file error LNK2001: Nichtaufgelöstes externes Symbol "struct _iobuf * __cdecl _wfopen(unsigned short const *,unsigned short const *)" (?_wfopen@@$$J0YAPAU_iobuf@@PBG0@Z)

Does anyone know a solution? I must use fopen, because I need a FILE* for an input in an imported C-dll.

toxcct25-Feb-04 2:27

toxcct

25-Feb-04 2:27

is _wfopen similar to fopen ???

TOXCCT alias Nicolas C.

torrud25-Feb-04 2:36

25-Feb-04 2:36

_wfopen and fopen are the same. Only the input parameters are different.

FILE *fopen(
const char *filename,
const char *mode
);
FILE *_wfopen(
const wchar_t *filename,
const wchar_t *mode
);

I can use fopen or _wfopen. Always the compiler error occures.

Any solutions?

toxcct25-Feb-04 2:49

toxcct

25-Feb-04 2:49

no, not at all...

(you certainly included the correct header file, didn't you?)

TOXCCT alias Nicolas C.

torrud25-Feb-04 2:57

25-Feb-04 2:57

I think I have. Here my .cpp file:

#include "stdafx.h"
#include <stdio.h>
#using <mscorlib.dll>

#include "file.h"

using namespace System;
using namespace System::Runtime::InteropServices;

int file::Class1::createfile()
{
FILE* f = _wfopen(L"C:\\test.test", L"w+");
return 0;
}

And my header-file is:

#pragma once

using namespace System;

namespace file
{
public __gc class Class1
{
public :
int createfile();
};
}

David Crow25-Feb-04 3:02

David Crow

25-Feb-04 3:02

Does this help?

"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

Prakash Nadar25-Feb-04 3:12

Prakash Nadar

25-Feb-04 3:12

Just check in the MSDN what .lib files need to be added for its linking.

I have lost more blood shaving than on the battlefield - Adolf Hitler

torrud25-Feb-04 3:51

file-based database programming in VC++

25-Feb-04 3:51

Thanks for reply, but I can't extract the related information I need from MSDN. If I try to make a .NET-application using Visual C++, fopen works great. Only if I want to use that in a .NET-dll it doesn't work. Can anyone correct this code, so it will runnning as a .NET-dll, please?

My header-file:

// file.h

#pragma once
using namespace System;

namespace file
{
public __gc class Class1
{
public :
int createfile();
};
}

My implementation-file:

// file.cpp.

#include "stdafx.h"
#include <stdio.h>
#using <mscorlib.dll>

#include "file.h"

using namespace System;

int file::Class1::createfile()
{
FILE* f = fopen("C:\\test.test", "w+");
fclose(f);
return 0;
}

I'm trying and trying and get no solution. Please, it's important for me.

ppp00125-Feb-04 0:41

ppp001

25-Feb-04 0:41

Hi,

i need to implement simple database function in a VC++ application,
but i cannot include any database product like Access etc.
So i need to use file-based database, are there any efficient
(fast, robust and reliable) programming technique for implementing
a simple file-based database function?

Thanks

Re: file-based database programming in VC++

KarstenK25-Feb-04 0:54

KarstenK

25-Feb-04 0:54

If it is a really a simple db you can use an array of your db sets as ojects. If it is more maybe you can use the ODBC interface.

Try this @ home. (B&B)

Re: file-based database programming in VC++

roel_25-Feb-04 1:58

Re: file-based database programming in VC++

25-Feb-04 1:58

Have a look at sqlite - http://www.hwaci.com/sw/sqlite/

basementman25-Feb-04 10:17

basementman

25-Feb-04 10:17

You can use access db's without installing the Access product. All you need to install is the JET drivers (included in MDAC, which is FREE).

Alternatively, you could use your own classes and serialize them via MFC or memory-mapped files or even write a simple DBF file implementation.

onwards and upwards...

writing in a wave file

zizoo24-Feb-04 23:59

zizoo

24-Feb-04 23:59

This is my quest: I open a wave in a read/write mode,I create a new file, I modify the stored data by means of special interpolation, but when I finish I'd like to have a new wave file, but how to get it in the format Wave? I mean the header (44bits)...etc

Zizoo

Re: writing in a wave file

roel_25-Feb-04 2:00