C / C++ / MFC Discussion Boards

Re: Read/Write C++ object members to ini file?

Todd Smith7-Nov-01 16:10

7-Nov-01 16:10

That doesn't really work for what I need.

So far what I've come up with is to use a #define and create a .inc file which I will include in a .h and a .cpp file. The .inc will do different things when it's in the .h vs. in the .cpp. When I include the .inc in a .h file it will declare the member variables. When I include the .inc in a .cpp file it will create code to add the member variables along with a name to a map or something. I haven't worked out the details yet.

Todd Smith

Re: Read/Write C++ object members to ini file?

Tomasz Sowinski8-Nov-01 0:03

Tomasz Sowinski

8-Nov-01 0:03

If you're using MFC and your object is derived from CObject you can use CArchive with CMemFile, then save the contents of CMemFile to .ini using CWinApp::[Get|Set]ProfileBinary.

Tomasz Sowinski -- http://www.shooltz.com

Re: Read/Write C++ object members to ini file?

Joaquín M López Muñoz8-Nov-01 3:42

Joaquín M López Muñoz

8-Nov-01 3:42

What you're after is called reflection, the ability to access in runtime to the structure of a class. Efforts devoted to achieve some sort of reflection in C++ are usually very far-fetched (look for OpenC++ and Meta Object Protocol (MOP), for instance). Nevertheless, it is possible that some kind of library exists fith more modest objectives that suits your needs.

Good luck

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

About CListCtrl

7-Nov-01 15:18

How can I drag icon in CListCtrl ? Just like Windows Desktop!

Re: About CListCtrl

Mukkie8-Nov-01 8:09

Mukkie

8-Nov-01 8:09

See MFCDRAG and maybe LISTHDR samples in MSDN. Maybe it will help.

CTreeCtrl with checkboxes

Crercio O. Silva7-Nov-01 14:55

Crercio O. Silva

7-Nov-01 14:55

Does anyone know how to detect if a item was checked or unchecked in a CTreeCtrl? I took a look at the CTreeCtrl and it seems that there are no messages for this kind of thing.

Re: CTreeCtrl with checkboxes

Tomasz Sowinski8-Nov-01 0:12

Tomasz Sowinski

8-Nov-01 0:12

Sorry - no special notification for that. You'll have to handle WM_LBUTTONDOWN and use CTreelCtrl::HitTest. If returned flags have TVHT_ONITEMSTATEICON bit set, it was a click on checkbox.

Tomasz Sowinski -- http://www.shooltz.com

dynamic memory allocate 2 dimensional arrays using 2 pointers

Shannon Mesquite7-Nov-01 14:18

Shannon Mesquite

7-Nov-01 14:18

I have an assignment about writing 2 dimensional arrays class Array2D, but I don't know the syntax for using int *iptr and int **array2D to dynamically allocate memory. The following is my program. The class interface and main driver given as it is. I couldn't really find the error on my class Array2D implementation part. Please help me out.

#include <iostream>
using namespace std;

#include <iomanip>

#include <cstdlib>
#include <cassert>
#include "PA_02.h"

//Output the array in row & column format (table format)
//Overloaded output operator for class Array2D
ostream &operator<<( ostream &out, const Array2D &obj )
{
for ( int i = 0; i < obj.rows; i++ )
{
for ( int j = 0; j < obj.cols; j++ )
out <<setw(10)<< obj.array2d[i][i];
="" out="" <<="" "\n"="" <<endl;
="" }

=""
="" return="" out;

="" input="" the="" entire="" array="" contents
="" overloaded="" operator="" for="" class="" array2d
="" istream="" &operator="">>( istream &in, Array2D &obj )
{
cout<<"Enter array values, one row at a time:\n"<<endl;
for="" (="" int="" i="0;" <="" obj.rows;="" i++="" )
="" {
="" cout<<"enter="" column="" values="" row="" "<<="" <<":\n"<<endl;
="" j="0;" obj.cols;="" j++="" cout="" <<"\nenter="" value="" ("="" <<="" <<"="" ,"="" <<")="" :";=""
="" in="">> obj.array2D[i][j];;
}

}
cout<<"\n\nInput complete\n"<<endl;
return="" in;
="" }

="" initialization="" and="" termination="" methods
=""
="" dynamically="" create="" an="" initialized="" array,="" contents="" will="" be="" to="" value
="" array2d::array2d(="" int="" r,="" c,="" value="" ):rows(r),="" cols(c)
="" {
="" i,="" j;="" iptr="new" int[="" r="" ];
="" assert(="" !="0);
" array2d="&iptr;
" for(="" i="0;" i<r;="" i++="" )
="" j="0;" j<c;="" j++="" array2d[i]="new" int[j];
="" );
="" }
="" }=""

="" initialize="" array="" equals="" 0
="" for="" (="" <="" r;="" c;="" array2d[i][j]="value;
" }

="" the="" copy="" constructor
="" const="" &rhs="" )="" :="" rows(="" rhs.rows),=""
cols(rhs.cols)
="" j;
="" rows="" rows;="" j<cols;="" rhs="" into="" object
="" cols;="" assignment="" operator="" (performs="" assignment)
="" &array2d::operator="(" j,="" i;
="" if="" check="" self="" assignment
="" delete="" []="" iptr;
="" cols="" array2d;
="" i<rows;="" *this;

="" clean="" up="" (e.g.="" allocated="" memory)
="" array2d::~array2d(="" void="" cout<<"\ndestructor="" called"<<endl;
="" =set="" get="" methods.="" explicitly="" whether="" index="" is="" within="" bounds="" of="" array

="" set="" item="" in="" at="" location(="" row,="" col="" ).
="" returns="" false="" out-of-bounds,="" else="" true
="" bool="" array2d::set(="" &new_item,="" if(="" row="">0 && col>0 )
{
for( int i=0; i<row; i++="" )
="" {
="" for(="" int="" j="0;" j<col;="" j++="" array2d[i][j]="new_item;
" }
="" return="" true;
="" else
="" false;
=""
="" }

="" get="" an="" item="" in="" the="" array="" at="" location="" (="" row,="" col="" ).
="" returns="" false="" if="" index="" is="" out-of-bounds,="" else="" true.
="" bool="" array2d::get(="" &item,="" )="" const
="" if(="" row="">0 && row<=rows )
{
if( col>0 && col<=cols )
{
for( int i=0; i<row; i++="" )
="" {
="" for(="" int="" j="0;" j<col;="" j++="" array2d[i][j]="item;
"
="" }
="" return="" true;
="" else
="" false;
="" }

="" returns="" the="" length="" of="" array
="" array2d::size(="" void="" )="" const
="" (="" sizeof(="" array2d[rows][cols]="" );
="" number="" rows
="" array2d::getrow(="" rows;
="" columns
="" array2d::getcol(="" cols;
="" compare="" this="" array="" with="" <rhs=""> for equality. Two arrays are equal if
//their
//rows, and cols are equal and all the elements are equal
bool Array2D::operator==( const Array2D &rhs ) const
{
if ( rows != rhs.rows && cols != rhs.cols )
return false; //arrays of different size

for ( int i = 0; i < rows; i++ )
{
for ( int j = 0; j < cols; j++ )
if ( array2D[i][j] != rhs.array2D[i][j] )
return false; //arrays are not equal

}
return true;
}

//Compare this array with <rhs> for inequality
bool Array2D::operator!=( const Array2D &rhs ) const
{
if ( rows == rhs.rows && cols == rhs.cols )
return false;

for ( int i = 0; i < rows; i++ )
{
for ( int j = 0; j < cols; j++ )
if ( array2D[i][j] == rhs.array2D[i][j] )
return false;
}

return true;
}

//Overload () to allow use of ( i, j ) notation ( leftvalue )
int &Array2D::operator()( int i, int j )
{
if ( i >= rows || j >= cols )
cout<<"out of bounds"<<endl;

="" return="" array2d[i][j];
="" }
="" overload="" ()="" to="" allow="" use="" of="" (="" i,="" j="" )="" notation="" rightvalue="" )
="" const="" int="" &array2d::operator()(="" const
="" {
="" if="" i="">= rows || j >= cols )
cout<<"out of bounds"<<endl;
return="" array2d[i][j];
="" }

="" utility="" functions

="" returns="" true="" if="" <index=""> is within range, else false
bool Array2D::in_range( int r, int c ) const
{
if ( r < 0 || r >= rows && c < 0 || c >= cols )
return false;
else
return true;

}

//Perform dynamic memory allocation
void Array2D::allocate( void )
{
rows = ( rows>0 ? rows Blush | :O

);
cols = ( cols>0 ? cols Blush | :O

);
iptr = new int[ rows ];
assert( iptr != 0 );
array2D = &iptr;
for( int i=0; i<rows; i++="" )
="" {
="" for(="" int="" j="0;" j<cols;="" j++="" array2d[i]="new" int[="" ];
="" assert(="" !="0" );
="" }
=""
="" }

--------------------------------------------------------------------------------

#include="" <iostream="">#include <cassert>
#include "PA_02.h"
#include "a2D.cpp"
using namespace std;

int main()
{
Array2D a1( 2, 3, 5 );
Array2D a2 = a1;
Array2D a3, a5( 4, 2, 3 );
Array2D a4( a3 );

//Test the << operator
cout<<"\nPrinting a1 ...\n"<<a1;
cout<<"\nprinting="" a2="" ...\n"<<a2;
="" a3="" ...\n"<<a3;
="" a4="" ...\n"<<a4;
="" a5="" ...\n"<<a5;

="" test="" the="">> operator
cin>>a3;
cout<<"\nPrinting a3 ...\n"<

Re: dynamic memory allocate 2 dimensional arrays using 2 pointers

8-Nov-01 3:23

You could save a lot of time by replacing the element of your matrix in a vector : let say you have a mxn matrix you just allocate a vector of size mn.
you can access the elements easily e.g. array[i*m+j]
Easier, faster, cleaner.

ps: by the way you have a bug in your << operator. [i][i] should be [i][j]

CreateProcess

7-Nov-01 12:27

I am running a multiproject application and in one of the projects, there is a Process created using CreateProcess. This process uses an executable created in another project of this same application to perform certain tasks.

I am under the impression that if I add "DEBUG_PROCESS" as one of the options under CreateProcess, I should be able to debug into the Process (i.e. Go F11 and right into the actual file).

However, what I seem to get is a program that sort of hangs when it gets to WaitForSingleObject statement.

Any ideas of how to debug into a Process? What am I doing wrong?

thanks

Re: CreateProcess

Masaaki Onishi7-Nov-01 15:59

Masaaki Onishi

7-Nov-01 15:59

Hello, the codegurus around the world.;)

I have the same problem to debug some project.
In this case, I wrote the following.

#ifndef _DEBUG
      WaitForSingleObject (...);
#endif

This approach will not solve the basic problem, but
we can debug the different EXE created by CreateProcess.

So, in the debug mode, we can teminate the main exe process by debug menu,
otherwise, we will get some messy situation since we never call WaitForSingleObject. Roll eyes | :rolleyes:

Have a nice day!

-Masaaki Onishi-

Password Edit & XP

7-Nov-01 12:17

I am using MFC for a XP program, and have various controls on the dialog box.

When I add my .manifest file, all the controls are displayed as they should be (flat, hot tracking etc), but if I add the style "ES_PASSWORD" to an Edit box, I don't get the '*' character or the XP black circle, instead I get a small black rectangle.

Help.

Joe.

Re: Password Edit & XP

Masaaki Onishi7-Nov-01 16:08

Masaaki Onishi

7-Nov-01 16:08

Hello, the codegurus around the world.;)

I think that this is normal since MFST seems to change the password
word from * to the black circle on XP.

Windows application depends on the core DLL of Windows, so
as long as we use DLL of XP, I think that we can't change this. Confused | :confused:

Have a nice day!

-Masaaki Onishi-

Entering a password in the Command Prompt

Alvaro Mendez7-Nov-01 11:50

Alvaro Mendez

7-Nov-01 11:50

A while back I posted this question here but no one replied. Let me try again...

I have a console app which prompts the user for a user id and password. The problem is that I don't know how to prevent the password from being displayed as the user types it. I'm using good old cin to retrieve it, like this:

cout << "Password: ";
 
char szPassword[80];
cin.getline(szPassword, sizeof(szPassword));

Is there a way to hide what the user types or perhaps mask it somehow?

Thanks,
Alvaro

Re: Entering a password in the Command Prompt

C^hris L^osinger7-Nov-01 12:02

C^hris L^osinger

7-Nov-01 12:02

char c = 0;
while (c!=' ')
{
   if(kbhit())
   {
      c=getch();
      printf("*");
   }
}

-c

POKE 808,234

Re: Entering a password in the Command Prompt

Alvaro Mendez7-Nov-01 12:17

Alvaro Mendez

7-Nov-01 12:17

Thanks for the quick answer Chris. Now, to throw a monkey wrench into the solution: it has to compile and run on both Windows and UNIX. Is there an equivalent to kbhit on UNIX?

Thanks again,
Alvaro

Re: Entering a password in the Command Prompt

Nish Nishant7-Nov-01 13:57

Nish Nishant

7-Nov-01 13:57

Alvaro

In windows you can do this :-

while((c=_getch())!='\n')
{
      printf("*");
      s[i++]=c;
}
s[i]='\0';

For Linux/Unix you'll need to write your own _getch() function.

You can do this with not too much difficulty

(1)First open /dev/tty
(2)use ioctl to change keyboard device parameters [there is some flag to prevent echoing]
(3)Then read one character
(4)use ioctl to set echo back
(5)Now close /dev/tty

I am sorry I couldnt actually put the code here, but if you have access to a unix box you can lookup ioctl and /dev/tty in the man pages and figure out a way.

Regards
Nish

Sonork ID 100.9786 voidmain

Re: Entering a password in the Command Prompt

Michael P Butler7-Nov-01 22:01

Michael P Butler

7-Nov-01 22:01

Unix/Linux does haven't a getch()!

I'd have thought with all those open source programmers they could get round to doing one of the most basic input functions. I'd have though getch() would have been part of the standard c library.

Michael Smile | :)

Re: Entering a password in the Command Prompt

Nish Nishant7-Nov-01 22:23

Nish Nishant

7-Nov-01 22:23

Thats cause in Linux they dont take passwords from the keyboard. They put it in a file and put the file in /etc and chown it to root and chmod it to 000

Nish

Sonork ID 100.9786 voidmain

Re: Entering a password in the Command Prompt

Alvaro Mendez8-Nov-01 5:28

Alvaro Mendez

8-Nov-01 5:28

Nish,

Thanks for your reply. I got it working on Windows, which by the way requires me to look for '\r' instead of '\n'. Now I'm trying UNIX but I'm lost:

(1)First open /dev/tty how? with fopen?
(2)use ioctl to change keyboard device parameters [there is some flag to prevent echoing] could not find such flag.
(3)Then read one character how? with fgetc?
(4)use ioctl to set echo back again, I don't know how
(5)Now close /dev/tty I imagine with fclose, but then what, repeat for the next character?

Thanks for your help,
Alvaro

Re: Entering a password in the Command Prompt

Alvaro Mendez8-Nov-01 6:16

Alvaro Mendez

8-Nov-01 6:16

Well, I got it working so that it doesn't show any characters. It's not as pretty as the masked solution, but it's easier and it works. Here's the code for the method, in case someone's interested:

string getPrompt(const char* szPrompt, bool bShow = true)
{
	cout << szPrompt << ": ";
 
	char szResponse[80];
 
	if (bShow)
		cin.getline(szResponse, sizeof(szResponse));
	else
	{
		#ifdef _WIN32
			int iPos = 0;
			for (int c = 0; (c = getch()) != '\r'; )
			{      
				if (c == '\b')
				{
					if (iPos > 0)
						iPos--;
				}
				else if (isprint(c) && iPos < sizeof(szResponse) - 1)
					szResponse[iPos++] = c;
			}
			szResponse[iPos] = 0;
		#else
			system("stty -echo");
			cin.getline(szResponse, sizeof(szResponse));
			system("stty echo");
		#endif
	}

	return szResponse;
}

Thanks for your assistance.
Alvaro

Re: Entering a password in the Command Prompt

Joaquín M López Muñoz7-Nov-01 12:20

Joaquín M López Muñoz

7-Nov-01 12:20

Not within iostream, I think. You'll have to capture keystrokes with _getch() and print out the asterisks yourself (handling backspaces is a little tricky, also).

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Loops and MFC?

7-Nov-01 11:16

How do i use loops in MFC?
Whenever i use a for loop my MFC program freezes!

thanks Smile | :)

Re: Loops and MFC?

Stan Shannon7-Nov-01 11:24

Stan Shannon

7-Nov-01 11:24

Could you post your code?

"But, daddy, that was back in the hippie ages..." My twelve year old son - winning the argument.

"Stan, you are an intelligent guy who responds in meaningful ways" Paul Watson 16/10/01

Re: Loops and MFC?

7-Nov-01 11:31

heres the code

do
{
if ((x % counter == 0) && (y % counter == 0))
{
x = x / counter;
y = y / counter;
}
counter -= 1;
}
while (counter > 0);

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.