Re: How to replace last line of a file? - C / C++ / MFC Discussion Boards

Re: how to trap command window that appears while executing a C++ prog...

ColinDavies27-Jul-02 0:13

27-Jul-02 0:13

Thst not such a bad idea, don't wast eiopportunities to flame folk to a crisp and rememeber to turn the over and flame the other side, its embarrassing to have folk turn up any the roast is only halve done.

Regardz
Colin J Davies

Sonork ID 100.9197:Colin

You are the intrepid one, always willing to leap into the fray! A serious character flaw, I might add, but entertaining.
Said byRoger Wright about me.

how to trap command window that appears while executing a C++ prog...

Pankaj Singh26-Jul-02 23:08

Pankaj Singh

26-Jul-02 23:08

I want to trap escape button like we do in Vb...

Eg.

when we write this under key press / keycode event in Vb..
if keyascii=27 then
unload me
exit sub
endif

How can I use CListCtrl's LVS_REPORT

Angel Kid26-Jul-02 22:16

Angel Kid

26-Jul-02 22:16

I want to use the CListCtrl's LVS_REPORT ,but I have no idea in using the CListCtrl,anyone could give me a sample or the setps? I could not understand the MSDN 's .Thank .

YES, I am here.

Re: How can I use CListCtrl's LVS_REPORT

Philip Patrick26-Jul-02 23:47

Philip Patrick

26-Jul-02 23:47

Well, if you already have your list control on your dialog, those are the steps: (I suppose that m_wndList is the CListCtrl

m_wndList.ModifyStyle(0, LVS_REPORT); //see CListCtrl::Create for other styles

<font color=green>//now have to add at least on column. We'll add 2 columns</font>
m_wndList.InsertColumn(0, "My name");
m_wndList.InsertColumn(1, "My phone");
<br>
<font color=green>//now we can add items, one after another.
//I use GetItemsCount to be sure that new items added at the end of list
//if you want to add at the beginning, just use 0 (zero) instead</font>
int nItem = m_wndList.InsertItem(m_wndList.GetItemsCount(), "Philip Patrick");
m_wndList.SetItem(nItem, 1, "111-111-222222");

That's all Smile | :)

Philip Patrick
Web-site: www.stpworks.com
"Two beer or not two beer?" Shakesbeer

thank you,your are really good!

Angel Kid27-Jul-02 4:33

Angel Kid

27-Jul-02 4:33

YES, I am here.

How to replace last line of a file?

Jon Taylor26-Jul-02 22:14

Jon Taylor

26-Jul-02 22:14

I'm working on an app that dumps loads of trace information to a file, as XML:

<log>
<message>
....
</message>
</log>

Now, when the app closes I write "</log>" as the last line. However, the next time the app is run, I want to append to this file, which means I must remove that last line. (It's the XML "root node" Smile | :)

)

Now, I know I can rename the file, re-parse it and re-write it etc but these log files reach 10's of Mb in size, so it takes too long to do that.

So I want to over-write the last line with some new text instead. I seem to remember doing this using the C standard library in the dim and distant past, but can I do this using the C++ library?!! Mad | :mad:

I've tried with the <fstream> library, and seekp() & tellp() but am getting a bit unstuck Unsure | :~

Any ideas anyone?

Re: How to replace last line of a file?

Nish Nishant26-Jul-02 22:40

Nish Nishant

26-Jul-02 22:40

Open the file using CreateFile. Now use SetFilePointer with the FILE_END flag. Now call SetFilePointer with FILE_CURRENT and use -8 as the lDistanceToMove value. Thus it moves back 8 bytes (</log>\r\n). If you have only a \n, then put -7 as lDistanceToMove. Now write your stuff and close the file.

Nish

Author of the romantic comedy

Summer Love and Some more Cricket [New Win]

Review by Shog⁹
Click here for review[NW]

Re: How to replace last line of a file?

l a u r e n27-Jul-02 1:10

l a u r e n

27-Jul-02 1:10

i think a slightly more robust way would be to read the last 100 bytes into memory and find the string and calc its offset and use that when seeking the file position ... unicode chars and whatnots might screw u up if u hard code the sizes into the algorithm

"... and so i said to him ... if it don't dance (or code) and you can't eat it either f**k it or throw it away"
sonork: 100.18128 8028finder.com

Re: How to replace last line of a file?

Sharad Ganesh27-Jul-02 4:11

Sharad Ganesh

27-Jul-02 4:11

hi,

If you're keen on using the C++ library, u could do this with fstream's ::seekg to seek to the end(ios::end) minus the offset which is calculated. The offset would be calculated using sizeof(string). Specify the offset in (-)ve. Now you can write the present contents from this location.

P.S. Open the file in binary mode.

hope this helps,
Sharad

In C you write your own bugs, in C++ you inherit them !
- Anonymous

cmb1 (and edt1) and OFN_EXPLORER

Atlantys26-Jul-02 21:08

Atlantys

26-Jul-02 21:08

So I've got this nifty CFileDialog-extended class that doesn't use the OFN_EXPLORER flag. I need to check the extension the user selected, so to do that, I look at the "cmb1" control (well, also some other Explorer-style control identifiers)

So everything was going well and good, until I found an article on how to allow CFileDialog-derived classes to use the OFN_EXPLORER flag (basically make the OPENFILENAME size 12bytes larger). And now the ASSERT fails. Cry | :((

CWnd* pComboBox = GetParent()->GetDlgItem(cmb1);
ASSERT_VALID(pComboBox);

So, if anyone can point me in the right direction, or just outright solve this problem, that would be great! (I'd rather not have to use Win32 to solve this though)
Thanks in advance.

GDI Rotation Question

jonbrown26-Jul-02 20:23

jonbrown

26-Jul-02 20:23

Hello all,

I am writing a little vector animation program and want to add rotation to my basic shapes. I have an algorithm that works ok... other than the fact that is shrinks the shape as it rotates! It works much better in OpenGL since its points are floating point. As far as I can tell, the shrinking is due to round off error, going from double to int. I am using the GDI in this case so I can't really do much about it. I am also programming this to run on both 9X and XP so no world transformations. I intend to make this method work for all gdi type basic shapes it is only working (appropriately) with the shapes that are invariant under rotation, the Polyxxxx shapes.

So, can anyone verify my diagnosis or point out other problems? Moreover, can anyone suggest a... less destructive way to rotate?

Thanks alot
////////////////////////////////////////////////////////////////////
int CShape::Rotate(int nAngle) // thar she be!
{
double dAngle = -nAngle * DEG_TO_RAD,
tX, tY, tX2, tY2;

for(int i = 0; i < m_aSourcePoints.GetSize(); i++)
{
tX = m_aPoints[i].x - m_ptRotate.x;
tY = m_aPoints[i].y - m_ptRotate.y;

tX2 = (int)((tX*cos(dAngle))-(tY*sin(dAngle)))+m_ptRotate.x;
tY2 = (int)((tX*sin(dAngle))+(tY*cos(dAngle)))+m_ptRotate.y;

//round the rotates point values
if((tX2 - floor(tX2)) >= 0.5) tX2 = ceil(tX2);
else tX2 = floor(tX2);
if((tY2 - floor(tY2)) >= 0.5) tY2 = ceil(tY2);
else tY2 = floor(tY2);

m_aPoints[i].x = tX2;
m_aPoints[i].y = tY2;
}
return ANI_OK;
}

jon brown

Help in CStatic

SamirSood26-Jul-02 19:30

SamirSood

26-Jul-02 19:30

I want to color a text in Static box on a dialog box with color of the static box same as the dialog box .

Can Anyone suggest a sololution for it. Smile | :)

Samir Sood

Re: Help in CStatic

l a u r e n27-Jul-02 1:18

l a u r e n

27-Jul-02 1:18

if you want to color statics you can either use one of the enhanced static controls here (norm almonds is a good one mostly) or you can override the OnCtlColor() function in your dialog box (the WM_CTLCOLOR message)
Cool | :cool:

"... and so i said to him ... if it don't dance (or code) and you can't eat it either f**k it or throw it away"
sonork: 100.18128 8028finder.com

Tiff image format and CMYK color mode

storein26-Jul-02 18:29

storein

26-Jul-02 18:29

I want to dispose tiff image file format .

and I have downloaded some source program ,but I find that this source code have a problem which it doesn't decode CMYK color mode TIFF file . then display CMYK tiff file is error .

do you know how to resolve it ?

thank you

Re: Tiff image format and CMYK color mode

storein26-Jul-02 18:55

storein

26-Jul-02 18:55

I want to read CMYK color mode TIFF file
and save CMYK color mode TIFF file
if I transform CMYK TIFF file to RGB file .
then color information will change .
(I use photoshop for testing)
So I want to dispose CMYK TIFF file in CMYK color mode .
no transform .

Re: Tiff image format and CMYK color mode

C^hris L^osinger27-Jul-02 5:46

C^hris L^osinger

27-Jul-02 5:46

get yourself a copy of LibTiff. with it, you can read and write the TIFF data directly.

-c

To explain Donald Knuth's relevance to computing is like explaining Paul's relevance to the Catholic Church. He isn't God, he isn't the Son of God, but he was sent by God to explain God to the masses.
/. #3848917

Fractals!

Re: Tiff image format and CMYK color mode

storein27-Jul-02 20:00

storein

27-Jul-02 20:00

Yes ,I have used Libtiff .
but it has the same quesiton .

Don't dispose correctly CMYK color mode Tiff Image

I need read and write CMYK color mode Tiff image .

and I have tested CXimage class that downloaded from http://www.codeproject.com/bitmap/cximage.asp
It supports Tiff file ,but there is a problem that It supports CMYK color mode tiff image.

and FreeImage Library ,download from
http://www.codetools.com/bitmap/graphicsuite.asp
it uses Libtiff library .but I find that there is the same problem of supporting CMYK color mode tiff file .

I don't know how to do

help me

Thank you

Help me .

storein28-Jul-02 16:47

storein

28-Jul-02 16:47

thank you Dead | X|

Re: Help me .

storein28-Jul-02 20:50

storein

28-Jul-02 20:50

Why nobody? Confused | :confused:

help me

Anonymous26-Jul-02 18:28

Anonymous

26-Jul-02 18:28

I want to get width and height of richedit control how to get it!
thanks

Re: help me

Ken Mazaika26-Jul-02 18:33

Ken Mazaika

26-Jul-02 18:33

Is there a getclientrect() member function? Just a guess....

-Ken Mazaika

Re: help me

perlmunger26-Jul-02 18:44

perlmunger

26-Jul-02 18:44

GetClientRect returns just the client area. GetWindowRect returns the area of the entire CWnd object. See API docs for CWnd.

Best Regards.

-Matt

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

The 3 great virtues of a programmer:
Laziness, Impatience, and Hubris.
--Larry Wall

Re: help me

Peter Occil26-Jul-02 18:52

Peter Occil

26-Jul-02 18:52

#define RectWidth(lprc) ((lprc)->right-(lprc)->left)
#define RectHeight(lprc) ((lprc)->bottom-(lprc)->top)

RECT rc;
int width,height;
GetWindowRect(hwndRichEdit,&rc);
width=RectWidth(&rc);
height=RectHeight(&rc);

Peter O.

Re: help me

perlmunger27-Jul-02 5:21

perlmunger

27-Jul-02 5:21

I'm curious as to why you would do it that way. This is not a criticism, just a curiosity.

Why couldn't you just use CRect instead? Also, why are you using the globally scoped GetWindowRect rather than the CWnd GetWindowRect? Is there a benefit to doing it that way?

Here's the way I would do it:

int width = 0, height = 0;
CRect rect;
GetWindowRect( rect ); // Single parameter CWnd::GetWindowRect
width = rect.Width();
height = rect.Height();

Thanks.

-Matt

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

The 3 great virtues of a programmer:
Laziness, Impatience, and Hubris.
--Larry Wall

Re: help me

Tim Smith27-Jul-02 5:25

Tim Smith

27-Jul-02 5:25

Maybe he isn't using MFC/WTL or doesn't want to force that dependency on others.

Tim Smith

"Programmers are always surrounded by complexity; we can not avoid it... If our basic tool, the language in which we design and code our programs, is also complicated, the language itself becomes part of the problem rather that part of the solution."
Hoare - 1980 ACM Turing Award Lecture

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