C / C++ / MFC

Re: looking for project to help with

22-Aug-05 5:34

Yeah, I'm kinda disappointed in myself. However, I did do some reasearch, and came to the conclusion that my math skills weren't up to par for that yet, so I would start teaching myself some more math stuff. I did buy some books to help, but I've been doing this very big FoxPro project since about that time, and it's been changed, re-changed, re-re-changed, etc. It's finally reached completion, and I'm about to change companies in 2 weeks, anyway. Plus, I didn't have a computer at home until a couple of weeks ago.

I haven't actually forgotten, and I think about it every time I see your name on one of the posts. I will still try to do it, otherwise I'll feel like I failed at something, which I hate. So yes, I have paused, but I still intend to complete the task.

My articles

www.stillwaterexpress.com

BlackDice

toxcct22-Aug-05 5:54

toxcct

22-Aug-05 5:54

don't mind man, it's not a big problem... actually, it would be very interresting to know how such mathematics are implemented, but i am far from this too anyway...

moreover, i'd like to add such a function to my VisualCalc, but as i didn't implement formal calculus yet, it's a far point too.

don't care, you didn't failed, i apreciate the help you proposed, and accept the fact that it is a very difficult point to implement, even for mathematicians i believe... (making maths, and implementing them make a big gap...).

thanks,

TOXCCT >>> GEII power
[toxcct][VisualCalc]

Tile Windows Horizontally and Tile Windows Vertically

Ali Niaz14-Oct-04 5:54

Ali Niaz

14-Oct-04 5:54

Can anybody point me to an example or show me how to create a "Window Tiling Function" in an MDI application in MFC. I basically want the same functionality that you get when you do "Tile Windows Horizantally", "Cascade Windows" etc.

thanks

ali

Re: Tile Windows Horizontally and Tile Windows Vertically

BlackDice14-Oct-04 6:35

Re: Tile Windows Horizontally and Tile Windows Vertically

14-Oct-04 6:35

In your mdi, find out what function that id for the actual menu item is mapped to, then look at the mfc source.

Who are all these people and what are they doing in my house?...Me in 30 years, inside a grocery store

bdiamond Sleepy | :zzz:

David Crow14-Oct-04 6:45

David Crow

14-Oct-04 6:45

Ali Niaz wrote:
I basically want the same functionality that you get when you do "Tile Windows Horizantally"...

Send a WM_MDITILE message and set wParam equal to MDITILE_HORIZONTAL.

Ali Niaz wrote:
..."Cascade Windows"

Send a WM_MDICASCADE message and set wParam equal to 0.

"When I was born I was so surprised that I didn't talk for a year and a half." - Gracie Allen

Exception object destroyed 3 times?

Bob Stanneveld14-Oct-04 5:36

Re: Exception object destroyed 3 times?

14-Oct-04 5:36

Hello,

Consider the following code:

<br />
class A<br />
{<br />
public:<br />
  A() {}<br />
  ~A() <br />
  { <br />
    static int i = 0;<br />
    std::cout << "Destructor called " << ++i << " time(s)" <br />
              << std::endl;<br />
  }<br />
};<br />
<br />
void main()<br />
{<br />
    try<br />
    {<br />
       throw A;<br />
    }<br />
    catch(A ex)<br />
    {<br />
    } <br />
}<br />

When I run the code, the output is the following:
Destructor called 1 time(s)
Destructor called 2 time(s)
Destructor called 3 time(s)
Press any key to continue

I can figure why the destructor is called 2 times, but why is it called the 3d time??? Confused | :confused:

Multiply it by infinity and take it beyond eternity and you'll still have no idea about what I'm talking about.

John M. Drescher14-Oct-04 6:25

John M. Drescher

14-Oct-04 6:25

It has to do with how many times the object is being copied. If you replace the code with the following it will only call the destructor 2 times:

class A
{
public:
A() {}
~A()
{
static int i = 0;
std::cout << "Destructor called " << ++i << " time(s)"
<< std::endl;
}
};

void main()
{
try
{
throw A();
}
catch(A & ex)
{
}
}

[EDIT]

Here is a version that will only be called once:

class A
{
public:
A() {}
~A()
{
static int i = 0;
std::cout << "Destructor called " << ++i << " time(s)"
<< std::endl;
}
};

void main()
{
try
{
throw new A();
}
catch(A * pEx)
{
delete pEx;
}
}

[/EDIT]

John

Re: Exception object destroyed 3 times?

Bob Stanneveld14-Oct-04 6:31

Cleanup of exception objects?

14-Oct-04 6:31

Thanks, this solved my issue with handles getting closed to often Big Grin | :-D

Multiply it by infinity and take it beyond eternity and you'll still have no idea about what I'm talking about.

Errors C2371 and C2512.

Cleber Marinho14-Oct-04 4:49

Cleber Marinho

14-Oct-04 4:49

Please, could someone explain me why there are errors in the following code?

#include <iostream>
#include <string>
using namespace std;

class Log
{
public:
explicit Log(const string& msg) { cout << msg << endl; }
};

int main()
{
string msg = "Hello, World!";

Log(msg.c_str()); // This Works...
Log(msg); // ... but this doesn't; Errors C2371 and C2512!

return 0;
}

I'm using VC++ .NET 2003.

Thanks in advance.

Bob Stanneveld14-Oct-04 3:44

14-Oct-04 3:44

Hello,

I, once again, am wondering about some C++ thing. This time it is about the cleanup of thrown exceptions.

Consider the following code:

<br />
// in some function an error condition is met<br />
throw new CSomeException(ErrorNumber);<br />
<br />
// in a try-catch block the exception is caught like this<br />
catch(CSomeException *pEx)<br />
{<br />
  // handle exception, don't call delete on pEx!<br />
}<br />

I want to know if the destructor is called when the catch-block is left, or does this lead to a memory leak?

Multiply it by infinity and take it beyond eternity and you'll still have no idea about what I'm talking about.

Nathan Holt at EMOM14-Oct-04 5:06

Nathan Holt at EMOM

14-Oct-04 5:06

Bob Stanneveld wrote:
I want to know if the destructor is called when the catch-block is left, or does this lead to a memory leak?

It leads to a memory leak. If someone throws a pointer to an exception, it won't automatically be deleted.

Nathan Holt

Bob Stanneveld14-Oct-04 5:16

14-Oct-04 5:16

Hello,

Thanks for the information. Big Grin | :-D

Multiply it by infinity and take it beyond eternity and you'll still have no idea about what I'm talking about.

Cleber Marinho14-Oct-04 5:11

Cleber Marinho

14-Oct-04 5:11

You can know this by yourself debugging. Put a breakpoint in your descructor, for exemple.

Bob Stanneveld14-Oct-04 5:21

char array -> system::string

14-Oct-04 5:21

I know, but I'm always looking for an excuse to surf to codeproject.com Poke tongue | ;-P

Multiply it by infinity and take it beyond eternity and you'll still have no idea about what I'm talking about.

Darcy P14-Oct-04 2:57

Darcy P

14-Oct-04 2:57

Hello, I'm using VC++ .NET 2003 and I'm fairly new to it and to GUI programming in general. For my current project I need to interact with some legacy C code that uses character arrays for strings.

I was able to convert from a system::string to a character array using the "PtrToStringChars" method but I can't, for the life of me, figure out how to convert an old-school char array back into a system::string.

Oh and the reasoning is that basically I need to parse a textbox in my form, convert the contents to a char array for the c code, then take a char array returned by the c code and convert it back to a managed string to be displayed in another textbox on the form. Make sense?

So... how do I do it!? Smile | :)

CString problem

Anonymous14-Oct-04 2:33

Anonymous

14-Oct-04 2:33

Dear Friends,

I got a CString. What i want to find out is whether the first character in that CString is a Number (i.e 0 to 9). How can i do so ??

David Crow14-Oct-04 2:42

David Crow

14-Oct-04 2:42

Use isdigit().

"When I was born I was so surprised that I didn't talk for a year and a half." - Gracie Allen

BlackDice14-Oct-04 3:01

14-Oct-04 3:01

Yes, use IsDigit(), and you can reference the first character of a CString like a char array (ie mystring[0])

[A brave person isn't always necessarily a smart person]

bdiamond Sleepy | :zzz:

Bob Stanneveld14-Oct-04 3:33

14-Oct-04 3:33

Yep

Multiply it by infinity and take it beyond eternity and you'll still have no idea about what I'm talking about.

Linking a C# dll into C++

hyling14-Oct-04 4:17

hyling

14-Oct-04 4:17

Cool!! Didn't know you could access it like an array. Big Grin | :-D

Member 131514814-Oct-04 2:21

Member 1315148

14-Oct-04 2:21

Does anyone know how to run a C# procedure that is located in a dll from a C++ .net dll?

Thanks
Max

DirectX CreateSurface question

Cedric Moonen14-Oct-04 2:03

Cedric Moonen

14-Oct-04 2:03

Hello !

I just started DirectX programming (based on samples I found on several websites). In fact I want to make a game (so in fullscreen mode). Everything is ok for that part but the problem when using this exclusive & fullscreen mode is that you cannot debug anymore (the screen remains black when a break point is reached in your code).

So I wanted to first start by using a windowed game for debugging purpose. But there the problem is when I try to create the front buffer using CreateSurface (with CooperativeLevel flags set to DDSCL_NORMAL):

     DDSURFACEDESC2		ddsd;<br />
   ZeroMemory( &ddsd, sizeof( ddsd ) );<br />
<br />
    ddsd.dwSize = sizeof( ddsd );<br />
    ddsd.dwFlags = DDSD_CAPS | DDSD_BACKBUFFERCOUNT;<br />
    <br />
	ddsd.ddsCaps.dwCaps = DDSCAPS_PRIMARYSURFACE |<br />
                          DDSCAPS_FLIP |<br />
                          DDSCAPS_COMPLEX;<br />
							<br />
    ddsd.dwBackBufferCount = 1;<br />
    <br />
	hRet = m_pDirectDraw->CreateSurface(&ddsd, &m_pFrontBuffer, NULL );

The function returns DDERR_NOEXCLUSIVEMODE ...

How can I solve the problem ??

Re: DirectX CreateSurface question

BlackDice14-Oct-04 3:03