C / C++ / MFC Discussion Boards

Nader Elshehabi3-Sep-06 4:40

3-Sep-06 4:40

Hello

Well, if you have some assembly background you'd remember that there is a bit in the status register called overflow bit to check for this error. Anyway, I know how to check for overflow in Assembly and C#, but sorry, my C++ is too rusty to remember how to do it in C++ Big Grin | :-D

.

You are right, there is a better way to detect overflow, yet I will provide you with a simpler way of detecting it. Usualy the overflow result is smaller than any of the two operands. So, try this:

ULONG size1 = 0xFFFFFF00;
ULONG size2 = 0xFFFFFF00;
size1 += size2; // == 0xFFFFFE00

if( size1 < size2)
    size1 = 0xFFFFFFFF;

Remember, maximum value of each type is totally OS dependant. Keep that in mind. Smile | :)

If someone got a better approach, please post. I'll try to remember how to check overflow in C++. If I got anything, I'll keep you posted.

Regards

Re: Adding two large numbers

Waldermort3-Sep-06 7:39

Waldermort

3-Sep-06 7:39

That probably is a better way of doing it. Thinking about it, the output would always be smaller. If you remember the better way, please post it. I would love to know.

Re: Adding two large numbers

toxcct3-Sep-06 5:24

toxcct

3-Sep-06 5:24

use the header <LIMITS.h>

with this, you can know the types max and min values, and some other informations for floating points types.

TOXCCT >>> GEII power

[VisualCalc 3.0 updated ][Flags Beginner's Guide new! ]

Re: Adding two large numbers

Rick York3-Sep-06 16:06

Rick York

3-Sep-06 16:06

You could do something like this :

_int64 sum = (_int64)size1 + (_int64)size2;
if( sum > ULONG_MAX )
TRACE( "an overflow occurred\n" );
else
size1 = (ULONG)sum;

Re: Adding two large numbers

Stephen Hewitt3-Sep-06 16:16

Stephen Hewitt

3-Sep-06 16:16

Try this:

ULONG size1 = 0xFFFFFF00;
ULONG size2 = 0xFFFFFF00;
ULONG sizeR = size1 + size2; // == 0xFFFFFE00
if (sizeR < max(size1, size2))
{
    // Overflow.
}

Steve

Re: Adding two large numbers

MayankT3-Sep-06 17:08

MayankT

3-Sep-06 17:08

try this:

<br />
if (MAXVAL - size1 < size2)<br />
{<br />
//overflow<br />
}<br />
else<br />
{<br />
size1 += size2;<br />
}<br />

MAXVAL can be obtained from limits.h as toxcct said.

----------------------
Mayank Thakore
Learning C++ - since 1998

They didn't print my card right; so I resigned.

CString to wchar_t*!!!!!!

mostafa_pasha3-Sep-06 3:13

mostafa_pasha

3-Sep-06 3:13

Hi,
how can i convert CString to wchar_t*? for example
CString m_strFilename;
how can i convert m_strFilename to wchar_t*?

i use L"" for string such that L"c:\filename.cpp", but is
there any function or macro do this?

Best Regards.
MJM

Re: CString to wchar_t*!!!!!!

Waldermort3-Sep-06 3:25

Waldermort

3-Sep-06 3:25

MultiByteToWideChar() is the function you want, but why not just use CStringW?

Re: CString to wchar_t*!!!!!!

mostafa_pasha3-Sep-06 3:33

mostafa_pasha

3-Sep-06 3:33

thanks , I use CStringW !

Re: CString to wchar_t*!!!!!!

messages3-Sep-06 7:50

messages

3-Sep-06 7:50

See

<br />
USES_CONVERSION;<br />
CString str;<br />
str="Test";<br />
<br />
wchar_t* m_wchar = T2W(str.GetBuffer());<br />
str.ReleaseBuffer();<br />
<br />

Re: CString to wchar_t*!!!!!!

Waldermort3-Sep-06 8:23

Waldermort

3-Sep-06 8:23

Which is almost exactly the same as what I told him. It's ok to use the conversion macros if you are doing a lot of converting, but for a single time it's pointless to add the extra header required.

Re: CString to wchar_t*!!!!!!

messages3-Sep-06 8:34

messages

3-Sep-06 8:34

Thanks for information

CAsyncSocket client

Cool^ASL3-Sep-06 2:35

Cool^ASL

3-Sep-06 2:35

Hi,
I have a client application in which i first do a Create() and then Connect() to connect to my server application.
The problem is that even if i dont start the server application, i get the Connect() return value as WSAEWOULDBLOCK and no other error value.

How do i determine correctly whether the server is actually available or not ? Am i doing anything wrong ?

Thanks in advance.

*** Who said nothing is impossible? I have been doing it for a long time ***

slow is normal?

milleusi3-Sep-06 2:26

milleusi

3-Sep-06 2:26

hi there

I'm a beginner in .net enviroment. I try to make a simple database application like this

http://www.functionx.com/vcnet/data...ridbinding3.htm

it's work's slowly. i'm waiting 5 seconds to make a simple select interogation. i have 3 entry's in that table

why that. what to do??

Re: slow is normal?

Hamid_RT3-Sep-06 22:38

Hamid_RT

3-Sep-06 22:38

Did you see examples in codeproject about databse

WhiteSky

How to draw horizontal line in dialog

Cool^ASL3-Sep-06 2:11

Cool^ASL

3-Sep-06 2:11

Hi,
I wish to draw a horizontal line in a dialog to delimit two sets of controls. But i cannot find any such thing on the tools panel.

Can anyone please help me out with that ?

Thanks in advance.

*** Who said nothing is impossible? I have been doing it for a long time ***

Re: How to draw horizontal line in dialog

Cedric Moonen3-Sep-06 2:21

Cedric Moonen

3-Sep-06 2:21

What I do generally (but maybe it's not the cleanest solution) is to put a picture control and reduce its vertical size to the minimum. Then I open the property dialog (right click on the control -> property) and I modify the style to be sunken. Like that you have a nice line.

Cédric Moonen
Software developer

Charting control [Updated - v1.1]

Re: How to draw horizontal line in dialog

Cool^ASL3-Sep-06 2:32

Cool^ASL

3-Sep-06 2:32

Thanks Cedric. that's a pretty nice trick.
Thanks a lot.

*** Who said nothing is impossible? I have been doing it for a long time ***

Re: How to draw horizontal line in dialog

_AnsHUMAN_ 3-Sep-06 18:20

_AnsHUMAN_

3-Sep-06 18:20

CoolASL wrote:
draw a horizontal line in a dialog

You can also do this:

HDC hdc=::GetDC (m_hWnd);
::MoveToEx (hdc,10,10,NULL);
::LineTo (hdc,100,10);
::ReleaseDC (m_hWnd,hdc);

Somethings seem HARD to do, until we know how to do them.
Wink | ;-)

_AnShUmAn_

Re: How to draw horizontal line in dialog

sheshidar3-Sep-06 19:52

sheshidar

3-Sep-06 19:52

Hi,
You better use group control
you can group the set of controls with this.

Re: How to draw horizontal line in dialog

Cool^ASL3-Sep-06 23:06

Cool^ASL

3-Sep-06 23:06

thanks man.

*** Who said nothing is impossible? I have been doing it for a long time ***

Re: How to draw horizontal line in dialog

Hamid_RT3-Sep-06 22:37

Hamid_RT

3-Sep-06 22:37

or you can use from a Static control with set Type to Etched Horz

WhiteSky

Re: How to draw horizontal line in dialog

Cool^ASL3-Sep-06 22:48

Cool^ASL

3-Sep-06 22:48

hi WhiteSky..
Thanks for the response.
Sorry, i couldnt get that property.
Can you please specify which VS version you are using.
I am using 2003.
Or is it that i am not looking in the right place.

Thanks.

*** Who said nothing is impossible? I have been doing it for a long time ***

Re: How to draw horizontal line in dialog

Hamid_RT3-Sep-06 22:55

Hamid_RT

3-Sep-06 22:55

When you insert picture control in your dialog then in property window set parameter Type->Etched Horz

WhiteSky

Re: How to draw horizontal line in dialog

MIAN KAMRAN6-Sep-06 1:56

MIAN KAMRAN

6-Sep-06 1:56

CPen pen(RGB(0,0,0));
CClientDC ccd(this);
ccd.SelectObject(&pen);
ccd.MoveTo(0,240);
ccd.LineTo(x,y); Smile | :)

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