C / C++ / MFC Discussion Boards

Cedric Moonen27-Jun-07 22:21

27-Jun-07 22:21

Because the macro L"..." (as you put it as argument to the MessageBox function) tells the compiler that the string literal (so the string that is between "") should be considered as a UNICODE string. A UNICODE string is a string that can display a larger set of character but also means that each character is encoded on two bytes instead of one. This string type is 'incompatible' with a standard char array (you cannot exchange from one to the other).
In fact, you won't have any error if you specified that UNICODE is enabled for your project. But in the case of VC6, the default is that UNICODE is disabled. If you used Visual Studio 2005, UNICODE is enabled by default.

Now, to avoid these kind of errors, use the _T macro instead. It will automatically take care of UNICODE setting enabled or not.

Cédric Moonen
Software developer

Charting control [v1.2]

Re: Simple Hello World Application

CPallini27-Jun-07 22:46

CPallini

27-Jun-07 22:46

MSDN [^]states: To specify a string of type wide-character (wchar_t[]), precede the opening double quotation mark with the character L. For example:

wchar_t wszStr[] = L"1a1g";

hence your string is a wide-character one, while the MessageBoxA (note the A suffix) is the ANSI version of the MessageBox, choosen by the compiler because you are making an ANSI build (the default one, on VC6). MessageBoxA accepts only ANSI strings (i.e. char *) while your strings are wide (i.e. unsigned short *), hence the error shows up.

Perhaps the sample code you used assumes you're using a later version of Visual Studio, that has UNICODE builds as default.

Hope that helps.
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.

Re: Simple Hello World Application

Michael Dunn28-Jun-07 8:10

Michael Dunn

28-Jun-07 8:10

See The Complete Guide to C++ Strings, Part I - Win32 Character Encodings[^]

Creating a new DSN

Pradosh Tapan Datta27-Jun-07 21:24

Pradosh Tapan Datta

27-Jun-07 21:24

Hi,

Can anybody help me out how to create a "Data Source Name" from my C++/MFC program?
I am using VC++8, Windows XP, and MySQL.

Pradosh

Re: Creating a new DSN

nitin327-Jun-07 21:31

nitin3

27-Jun-07 21:31

try
SQLConfigDataSource(...) API

Re: Creating a new DSN

Pradosh Tapan Datta27-Jun-07 23:14

Pradosh Tapan Datta

27-Jun-07 23:14

I was trying to get some help on SQLConfigDataSource(). I am not able to find any help in MSDN. Which header file it is belonging or so on so!

Currently I am using a reverse way to do the same:

<br />
system("odbcconf /S CONFIGDSN \"MySQL ODBC 3.51 Driver\" \"DSN=MyDsn | Description=test dsn | SERVER=10.1.1.4 | User=user1 | Password=pw1 | Database=MyDb\"");<br />

But I want to use any API to do the same.

Pradosh

Re: Creating a new DSN

nitin327-Jun-07 23:29

nitin3

27-Jun-07 23:29

imp lib: ODBCCP32.lib
include file : "odbcinst.h"

ref:
http://www.codeguru.com/cpp/data/mfc_database/microsoftaccess/article.php/c1135/

This creates a new DSN

Programm3r28-Jun-07 1:38

Programm3r

28-Jun-07 1:38

/**********************************************************************************
# FUNCTION NAME			: CREATEDSN
# PAREMETERS			: driver, keyword
# PARAMETER DATATYPES		: ALL CHARACTER POINTERS
# RETURN TYPE			: INTEGER
# USE				: Create a system dsn
**********************************************************************************/
extern "C" int sqlClass::createDSN(char* driver, char* keyword)
{
	//creating a return value variable
	int returnValue;
	try
	{
		//create a systems dsn - specify a driver and a keyword -> connection string
		returnValue = SQLConfigDataSource(NULL,ODBC_ADD_SYS_DSN,(LPSTR)driver,(LPSTR)keyword);
		if (returnValue)
			return 0;
		return -1;
	}
	catch(...)
	{
		//display a message to user if a exception occured
		MessageBox(NULL,"Exception Occured - DSN not created","Error Occured",MB_ICONHAND);
		return -2;
	}
}

The only programmers that are better than C programmers are those who code in 1's and 0's..... Smile | :)

Programm3r
My Blog: ^_^

Re: This creates a new DSN

Mark Salsbery28-Jun-07 6:44

Mark Salsbery

28-Jun-07 6:44

I'm curious....does SQLConfigDataSource throw exceptions? You have it wrapped in a try block.

Mark

"Go that way, really fast. If something gets in your way, turn."

File Encryption

danasegaranea27-Jun-07 21:22

danasegaranea

27-Jun-07 21:22

Hi all,
I need some good file encryption with password.Can you some suggest some thing.Please note that I am new to VC++

Dana

DES / 3DES / TEA ...

zhang80060527-Jun-07 22:15

zhang800605

27-Jun-07 22:15

There are general way to Encrypt .

chinese web
http://www.sfcode.cn/soft/00262.htm[^]

Re: DES / 3DES / TEA ...

danasegaranea27-Jun-07 23:13

danasegaranea

27-Jun-07 23:13

I don't know chinese.Not able to read the web site content/

mfc in vista

deeps_cute27-Jun-07 21:10

deeps_cute

27-Jun-07 21:10

i have created a mfc code in windows vista. but i cant run it in debug mode. it shows
"The ordinal could not be losded in the dynamic link library MFC42D.DLL". but it is successfully running in release mode. what to do for this, pls help me

Arise Awake Stop Not Till ur Goal is Reached.

Re: mfc in vista

Hans Dietrich27-Jun-07 21:21

Hans Dietrich

27-Jun-07 21:21

XP and Vista installations include the VS6 MFC release-mode Dlls, but not the debug-mode DLLs. You have to copy the MFC debug DLLs to the machine where you want to run. To find out which DLLs you will need, google for the dependency checker program Depends.exe.

Best wishes,
Hans

[CodeProject Forum Guidelines] [How To Ask A Question] [My Articles]

copy msc42d.dll to system32 directory

zhang80060527-Jun-07 21:26

zhang800605

27-Jun-07 21:26

Find out MFC42D.dll , and copy to system32 directory .

How to manage resouce? Make them unreadable to user.

Peter, Chan27-Jun-07 21:04

Peter, Chan

27-Jun-07 21:04

In my program I have used a lot of resouce. Such as: image(bmp, gif,...), config file(xml, txt, ini).There are more than 100 images and 10 config-files which is saved in a lot of folders. Now I don't want the user directly change or see these images and config files. Is there any way to package or make these resource unreadable.

Currently, my resources are all in the folder.I haven't compile them into my program.

I know vc6.0 can manage the resource. But it is still too weak for me. I want to manage my resource like a tree. Can add a directory or resource just as I want.

Maybe I will have to develop a resource manage tool.

VISTA

VC_RYK27-Jun-07 20:51

VC_RYK

27-Jun-07 20:51

I have created the appliaction for 2000/XP 32 bits. And i want to run my Application on Vista so what are the changes that i have to make my application Vista compitible.

Note :-I am using Visual srudio 2005

With Regards
RYK

Re: VISTA

Hans Dietrich27-Jun-07 21:26

Hans Dietrich

27-Jun-07 21:26

VC_RYK wrote:
what are the changes that i have to make

With luck, none at all. Most XP programs will work fine, although with some annoying UAC messages. You will have to try it and see.

Best wishes,
Hans

[CodeProject Forum Guidelines] [How To Ask A Question] [My Articles]

OnCtlColor

sudheee27-Jun-07 20:50

sudheee

27-Jun-07 20:50

what is the purpose of OnCtlColor
i have used one brush in onctlcolor and i am returning the handle of that brush.
cos of that GDI objects(can see in task manager) are going on increasing and memory usage is also increasing.
if i comment that brush everything is ok.. nothing is increasing. but in my application i must use that brush to draw the whole application.

can anyone give me solution to solve that problem

regards
sudhakar

Re: OnCtlColor

KarstenK27-Jun-07 21:00

KarstenK

27-Jun-07 21:00

make the brush a member of your Window class!

what is the purpose of OnCtlColor=> RTFM

Greetings from Germany

Re: OnCtlColor

sudheee27-Jun-07 22:57

sudheee

27-Jun-07 22:57

i need to change the color of the the entire dialog not only the controls on that dialog.

regards
sudhakar

Re: OnCtlColor

KarstenK27-Jun-07 23:12

KarstenK

27-Jun-07 23:12

The background can you paint in OnEraseBkgnd() Sleepy | :zzz:

Greetings from Germany

Re: OnCtlColor

alias_rizwan28-Jun-07 0:26

alias_rizwan

28-Jun-07 0:26

I guess you are creating a new brush in every time in OnCtlColor function.
if yes a simple solution would be to
1>make the brush object as a memeber of a classs
2>create thebrush object only once say in the constructor.
3>return the same handle every time in the function.
4>delete the object in the destructor.

Thanks
Rizwan

Thread Question

Programm3r27-Jun-07 20:47

Programm3r

27-Jun-07 20:47

Hi all,

Lets say one has created a thread using _beginthread() and now that thread is active and running. Now one wants to pass arguments to that thread function, but remember that the thread was already created. Now ... how can one (if it is possible) call that thread function, without calling _beginthread() again.
I.E

int callThreadFunc()
{
 // call thread function without calling _beginthrad
 // or can one just dio a nornal function call??? 
}
void myThread(void* a)
{
 while (1)
 {
   // do some stuff - not relevent
   Sleep(1000);
 } 
}
void main()
{
 _beginthread(myThread, NULL, 0); // creating the thread
 ...
}

Many Thanks
Regards,

The only programmers that are better than C programmers are those who code in 1's and 0's..... Smile | :)

Programm3r
My Blog: ^_^

Re: Thread Question

KarstenK27-Jun-07 20:57

KarstenK

27-Jun-07 20:57

with global variables, but you have the problem of syncronizing. If threads work together you need to syncronize them!!! Everything else is crap. Mad | :mad:

For instance with WaitForMultipleEvent()

Greetings from Germany

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