C / C++ / MFC Discussion Boards

David Crow30-Jun-03 8:20

30-Jun-03 8:20

void function(LPTSTR stringthing)
{
    string filename = "stringdata.dat", str;
    ifstream inFile(filename.c_str());
    inFile >> str;
    strcpy(stringthing, str.c_str());
}

Re: COnvert CEdit to string

keegan30-Jun-03 9:09

keegan

30-Jun-03 9:09

thanksa again, but that code returned an erro saying i cant convert from LPCSTR to char*.

i've foudn a way (the only way that my program can be run in another area of the code) where all i have to do is return a CString. but, this takes me back to teh beginning, because i cant use infile>> for a cstring object, i cant convert a string into a cstring if i try infile >> string, and i cant convert from a string to an LPCSTR if i try inFile >> string.

buggar this is annoying. why cant i just go

CString foo;
string bar;

infile >> bar;

foo = bar;

return foo;

*.*

Re: COnvert CEdit to string

David Crow30-Jun-03 9:53

David Crow

30-Jun-03 9:53

I don't know what it is you are trying to do, but all of my suggestions have been tried and tested with positive results. I'm sure there are better ways of accomplishing the task but these are answers to your question(s) nonetheless.

void function( LPTSTR stringthing )
{
    string filename = "stringdata.dat", str;
    ifstream inFile(filename.c_str());
    inFile >> str;
    strcpy(stringthing, str.c_str()); // this line can actually be omitted and use 'stringthing' in place of 'str' above
}

void main( void )
{
    char buf[1024];
    function(buf);
    printf("]%s[\n", buf);
}

When the answer appears to be wrong, don't discount the possibility that the wrong question was asked! - Anonymous

Re: COnvert CEdit to string

keegan30-Jun-03 9:58

keegan

30-Jun-03 9:58

all done!

thanks david Smile | :)

*.*

DirectDraw Palette

Kuniva30-Jun-03 6:07

Kuniva

30-Jun-03 6:07

I have a very basic DirectX app which just draws a number of surfaces on the screen from bitmaps. However if i don't first set a palette to the display, the colors are awfully messed up. I can then use CreatePaletteFromBitmap() to create a palette and attach it and then they are better. But the problem is that i'm drawing several piecies of an image seperately so they form one large image so i can only create a palette from one of these pieces, so other piecies can contain other colors so the end result will be that some colors still aren't perfect. How should i handle this? Should i make a small bitmap that has all the colors that are used in paint shop pro or something and create the palette from there? Or can you skip the palette, but do the bitmaps need a different color mode or something?

Kuniva
--------------------------------------------

Debugger won't startup when app crashes

John Oliver30-Jun-03 6:01

John Oliver

30-Jun-03 6:01

Could somebody tell me what string's they have in this key....

HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\AeDebug

for 'Debugger' and 'PreVisualStudio7Debugger'.

I tried to get rid of the splash screen appearing whenever VS JIT debugging starts up, as described in Wintellect article[^]but whatever I've done, the debugger won't start up at all now. I'm using VC++6 in VS6 btw

Thanks,john

Re: Debugger won't startup when app crashes

David Crow30-Jun-03 7:32

David Crow

30-Jun-03 7:32

I don't have those values. Perhaps one of these MSDN articles will be of help:

Q103861
Q188296
Q175644
Q121434
Q172779
Q138786

Re: Debugger won't startup when app crashes

John Oliver30-Jun-03 21:44

John Oliver

30-Jun-03 21:44

Thanks David, got the info i needed in Q103861

Virtual KeyCodes error: undeclared identifier

fluxt30-Jun-03 5:48

fluxt

30-Jun-03 5:48

For some reason, Visual Studio 6 is not recognizing the VK_* virtual key codes as being defined, even though they should be defined by default, and I added the line #include <winuser.h> and even added the .h file to my project... bah! What should I try? Thanks!

Re: Virtual KeyCodes error: undeclared identifier

valikac30-Jun-03 6:33

valikac

30-Jun-03 6:33

What key? Post the code and the error.

Kuphryn

Comparison in Preprocessor

chris_mccc30-Jun-03 4:59

chris_mccc

30-Jun-03 4:59

I'm having trouble comparing two Floating Point Const at Compile time. Here is an example:

const Float64 EducationGoal_Original = 0.0;
const Float64 EducationGoal_1_0 = 1.0;
const Float64 EducationGoal_2_0 = 2.0;
const Float64 EducationGoal_CURRENT = EducationGoal_2_0;
.
.
.
#if EducationGoal_CURRENT != EducationGoal_2_0
// return error
#endif

So...basically if someone adds a new EducationGoal version i want to make sure he updated all the code associated with it.

For some reason, the #if will always return true with floating point #s

Any Ideas?

Re: Comparison in Preprocessor

João Paulo Figueira30-Jun-03 5:14

João Paulo Figueira

30-Jun-03 5:14

I'm not sure that the preprocessor can read into a value of a const... Unsure | :~

Anyway, try to replace the const definition by a #define. I know this is not the correct way to create constants, but use it to check if the #if works.

Re: Comparison in Preprocessor

Ryan Binns30-Jun-03 5:14

Ryan Binns

30-Jun-03 5:14

You can't compare like that. To compare in the preprocessor, you need to #define the constants. const floats are not recognised by the preprocessor. Their "value" is 1 if they exist, and 0 if they do not (I think, from memory). To get this to work, use:

#define EducationGoal_Original (0.0);
#define EducationGoal_1_0 (1.0);
#define EducationGoal_2_0 (2.0);
#define EducationGoal_CURRENT (EducationGoal_2_0);
.
.
.
#if EducationGoal_CURRENT != EducationGoal_2_0
// return error
#endif

Even better would be to use integers, separated into major and minor version numbers, since floats are not accurate, and comparing them for equality is not a good idea.

Hope this helps,

Ryan

Being little and getting pushed around by big guys all my life I guess I compensate by pushing electrons and holes around. What a bully I am, but I do enjoy making subatomic particles hop at my bidding - Roger Wright (2^nd April 2003, The Lounge)

Punctuality is only a virtue for those who aren't smart enough to think of good excuses for being late - John Nichol "Point Of Impact"

(URGENT !!!!) Sharing Memory between CV++ 6.0 and VB 6.0

Carlo30-Jun-03 4:07

Carlo

30-Jun-03 4:07

Hi all,
I have this big problem:
from an exe written in VB i call a function in a Dll written in VC++. This function must allocate an array of structs ant restitute it initializad to the calling process.
To be more clear I'll write what I would do if the exe is in C++:

The struct could be something like this:
struct _Data
{
int Data1;
VARIANT Data2;
};

In the dll there is a function like this:
extern "C" void WINAPI DLLReadArray(_Data **Array)
{
*Array= new _Data[10];

// For example I fill the array elements whith some data
}

from the VC++ exe I would do something like:
void CallDLL()
{
_Data *Array;
DLLReadArray(&Array);

// Some operations on the array elements...

delete[] Array;
}

NOW:
I do not have any idea on how to do the last thing if the exe is written in VB.

The structure in VB could be declared as a Type ???
Type Data
Data1 As Integer
Data2 As Variant
End Type

How to pass the DLL a "pointer" in VB ????

Please, any help would be very very appreciated !!!
thanks all.

Sorry for my poor english.
Carlo Comino
Italy.

Re: (URGENT !!!!) Sharing Memory between CV++ 6.0 and VB 6.0

basementman30-Jun-03 4:27

basementman

30-Jun-03 4:27

The only method (that i'm aware of) to pass arrays between VB and VC is via SafeArrays. VB uses SafeArrays internally, so the work is on the C side to unpackage/use the data in this format.

onwards and upwards...

Re: (URGENT !!!!) Sharing Memory between CV++ 6.0 and VB 6.0

Carlo30-Jun-03 5:01

Carlo

30-Jun-03 5:01

thank yuo very much for your fast replay !!;)
Do you also have an example of the C part ??
thank you again!!
Carlo.

List Control in ATL/WTL

YaronNir30-Jun-03 4:05

YaronNir

30-Jun-03 4:05

Hi all,

i have an ATL project. i've created a dialog that inherites CAxDialogImpl.
in the resources of the dialog i've placed a list control.

is there a class that wrapps it in ATL? same as CListCtrl in MFC???

can any1 help?

thanks in advanced,

Yaron

Ask not what your application can do for you,
Ask what you can do for your application

Re: List Control in ATL/WTL

João Paulo Figueira30-Jun-03 4:47

João Paulo Figueira

30-Jun-03 4:47

Check the WTL header (AtlCtrls.h). There you should find a template <class TBase> class CListViewCtrlT which in turn will be specialized into a CListViewCtrl.

Re: List Control in ATL/WTL

YaronNir30-Jun-03 4:56

YaronNir

30-Jun-03 4:56

thanks man.....

Ask not what your application can do for you,
Ask what you can do for your application

Using Windows Access Control in my application

Mike Eriksson30-Jun-03 4:04

Mike Eriksson

30-Jun-03 4:04

Hello!

I have an application where different groups can do different things. E.g. Group Sales can add an customer. Group Pack can print out a pack order but not add a customer. etc...

I could of cause create my own control system but since Windows already has this kind of system and it is probably much better (security wise) than anything I could create.

How do I use Windows Access Control System in my own application?

I need to be able to create a number of groups and give them rights in my application.

TIA

Anders Eriksson
Sonork 100.21825

Re: Using Windows Access Control in my application

basementman30-Jun-03 4:32

basementman

30-Jun-03 4:32

If this is a SQL Server app, I would suggest looking at the TSQL function IS_MEMBER ({'group' | 'role' }). This provides rights / membership checking of both WindowsNT groups and SQL Server Roles.

Otherwise, you can use the NetGroupXXX functions, but your app needs to be running under certain priviledges and this is a pain.

onwards and upwards...

I wrote the buf[] question, Forgot to login

johnstonsk30-Jun-03 4:02

johnstonsk

30-Jun-03 4:02

Re: I wrote the buf[] question, Forgot to login

Trollslayer30-Jun-03 5:38

Trollslayer

30-Jun-03 5:38

Posted a reply, see below Big Grin | :-D

The tigress is here Big Grin | :-D

XP zip

_Magnus_30-Jun-03 4:01

_Magnus_

30-Jun-03 4:01

Anyone know if there is some API for the zip features in XP? Unsure | :~

/Magnus

- I don't necessarily agree with everything I say

Re: XP zip

Neville Franks30-Jun-03 11:53

Neville Franks

30-Jun-03 11:53

_Magnus_ wrote:
Anyone know if there is some API for the zip features in XP?

I don't think so. There are several articles here at CP re. zip/unzip and you can also look at Crypto++ which has this.

Neville Franks, Author of ED for Windows. Free Trial at www.getsoft.com

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