Re: How can I intercept the "Windows" menu - C / C++ / MFC Discussion Boards

PradeepKK1-Feb-06 23:49

1-Feb-06 23:49

Hi,

I am using ReadFile() method passing OVERLAPPED structure for reading from a socket in Asynchronous mode. Also i am using IO Completion ports for I/O notification. Is it possible that the ReadFile() can fail due to timeouts?.ie. If the packet that i am reading takes a lot of time to arrive, in that case will the ReadFile() fail?.

If indeed ReadFile() fails due to timeouts, how can i get that error information?.

Thanks in advance,
Pradeep

Re: Asynchronous I/O using ReadFile

Vanting2-Feb-06 0:45

Vanting

2-Feb-06 0:45

Hi,

You can use GetOverlappedResult(...)to retrive status of an OVERLAPPED operation

Or try loking af GetQueuedCompletionStatus(...)

Thomas

Re: Asynchronous I/O using ReadFile

PradeepKK2-Feb-06 1:18

PradeepKK

2-Feb-06 1:18

Hi,

Thanks for your help.

Also can any one pls let me know where i can find the documentation on OVERLAPPED structure.

typedef struct _OVERLAPPED {
DWORD Internal; // [out] Error code
DWORD InternalHigh; // [out] Number of bytes transferred
DWORD Offset; // [in] Low 32-bit file offset
DWORD OffsetHigh; // [in] High 32-bit file offset
HANDLE hEvent; // [in] Event handle or data
} OVERLAPPED, *LPOVERLAPPED;

In Programming Server Side Applications for Win2k by Jeffrey Richter, there is explanation about the OVERLAPPED structure. But, it doesn't explain more about the variable "DWORD Internal; // [out] Error code" and especially what values it can take.

Pls let me know where i can find the information. I have already searched msdn but of no use.

Thanks in advance,
Pradeep

Re: Asynchronous I/O using ReadFile

Iain Clarke, Warrior Programmer2-Feb-06 5:16

Iain Clarke, Warrior Programmer

2-Feb-06 5:16

Names like dwInternal are deliberately not explained. If you find out what it does, and start relying on that behaviour, who will get the blame when that undocumented behaviour changed in (eg) Vista?

(a) I used variables marked Reserved for operating system use, so its my fault when the application fails in five years. I will of course provide that length of future support.

OR

(b) Its that evil Micro$oft. How dare they change the function of these variables, breaking my application!

Don't take this polemic too personally. But I read too many examples tampering with internal structures...
Old New Thing is a good blog to read about this.

Iain.

How can I intercept the "Windows" menu

Jim @ JCT1-Feb-06 23:17

Jim @ JCT

1-Feb-06 23:17

Hi,

I wonder if anyone here knows how to intercept the "activate window" items on the Windows menu of a standard MFC app? You know the ones, the list of MDI client windows with the hint "Activate this window"?

If anyone knows it would be most useful to me,
Thanks.

Jim

Re: How can I intercept the "Windows" menu

Iain Clarke, Warrior Programmer2-Feb-06 6:17

Iain Clarke, Warrior Programmer

2-Feb-06 6:17

Looking through my string resources, I find "Activate this window" is String Resource with an ID of AFX_IDS_MDICHILD.

If you want to change it to another constant string, just change this string resource.

If you want it to be more dynamic, you will need to override void CFrameWnd::OnMenuSelect(UINT nItemID, UINT nFlags, HMENU hSysMenu,
which looks a bit more complex...

If you are more specific about what you want to change to, I/we may be able to help more.
Iain.

Re: How can I intercept the "Windows" menu

Jim @ JCT2-Feb-06 22:21

Jim @ JCT

2-Feb-06 22:21

The problem we are attacking is to do with the fact that our document format saves the positions of the child windows. Our application is a traffic engineering program and it uses a lot of different views, each in a child window. For this reason we recommend our users to use a dual-monitor system.
We want to deal with a posible situation where a user is running on a two monitor system and passes a file to a user with only one: some of the windows could disappear off screen. We cannot make them reposition when they get the focus as the user may wish to move the window off screen for a few moments while they are working and we don't want windows jumping about all over the place.
We just want the windows to reposition when the user activates the window... so this is why we want to intercept the 'Windows' menu.

Thanks for your reply, I'll take a look at using CFrameWnd::OnMenuSelect and see if I can make that work.

Thanks!
Jim

Re: How can I intercept the "Windows" menu

Iain Clarke, Warrior Programmer3-Feb-06 0:33

Iain Clarke, Warrior Programmer

3-Feb-06 0:33

In that case, I'd look at the command value(s) that "window 1", "window 2", etc pass. These will go through the normal command routing mechanism.
I've just looked, and the first window command is
#define AFX_IDM_FIRST_MDICHILD 0xFF00 // window list starts here

You could use

ON_COMMAND_RANGE_EX (AFX_IDM_FIRST_MDICHILD, AFX_IDM_FIRST_MDICHILD + 8, MyWindowHandler)
...
BOOL CMyFrame::MyWindowHandler (UINT nCmd)
{
    ....

    return FALSE; // Carry on handling this nmessage - maybe true to use.
}

I can't remember the exact details of the handler definition, or whether the return should be true or false, but you can do the legwork - I'm too lazy.

Probably simpler than getting a menuselect handler wrong!

Iain.

Re: How can I intercept the "Windows" menu

Jim @ JCT13-Feb-06 3:16

Jim @ JCT

13-Feb-06 3:16

Thanks to you pointing me in the right direction I was able to do it in the end:

<br />
BOOL CMainFrame::OnCommand(WPARAM wParam, LPARAM lParam)<br />
{<br />
    if (wParam >= AFX_IDM_FIRST_MDICHILD && wParam <= AFX_IDM_FIRST_MDICHILD + 8)<br />
    {               <br />
        //Get hold of a handle to the relevant window:<br />
        HWND hWnd = ::GetDlgItem(m_hWndMDIClient, wParam);<br />
        CMDIChildWnd* pChild = (CMDIChildWnd*)CWnd::FromHandlePermanent(hWnd);<br />
        <br />
        //Now do whatever it is I want to do with the window<br />
        pChild->DoWhatEver();<br />
    }<br />
<br />
    return __super::OnCommand(wParam, lParam);<br />
}

The trick was realising that GetDlgItem() works with MDI child windows.

Thanks for your help,
Jim

asking............

shazzney1-Feb-06 23:14

shazzney

1-Feb-06 23:14

good day to all of you!!!

by the way i have a trouble in understanding the timer botton in MFC coz im a beginner, then its really difficult for coz i dont have books, so please help me.

thank you so much.... i'll wait for ur reply

Re: asking............

RChin1-Feb-06 23:20

RChin

1-Feb-06 23:20

Are you asking what the equivalent in MFC of the VB timer event control?
AFAIK, MFC has no timer buttons.

I Dream of Absolute Zero

How to extract plain text from a url or a html document?

shertay1-Feb-06 21:02

shertay

1-Feb-06 21:02

I'm working on a project that extracts the content (plain text and preferably image) of a html document and a url. Does anyone know how any method to do so?

Re: How to extract plain text from a url or a html document?

Stephen Hewitt1-Feb-06 21:28

Stephen Hewitt

1-Feb-06 21:28

It depends on what you're using. Is you're using MSHTML then you could get the text by using the innerText property on the body element. In C++ using ATL this could look something like this:

HRESULT GetText(IHTMLDocument2* pDoc, BSTR* pTextOut)
{
     if ( pTextOut == NULL )
     {
         return E_POINTER;
     }
     *pTextOut = NULL;
 
     CComPtr<IHTMLElement> spBody;
     HRESULT hr = pDoc->get_body(&spBody);
     if ( FAILED(hr) )
     {
         return hr;
     }
 
     return spBody->get_innerText(pTextOut);
}

To get the images you can use the IHTMLDocument2::get_images method.

NOTE: I haven't tried this code!

Steve

Re: How to extract plain text from a url or a html document?

shertay5-Feb-06 16:47

shertay

5-Feb-06 16:47

Hmm how do i get the images from IHTMLElementCollection? I shld use image rite but what parameters do I have to pass?

Text extraction

KongHL1-Feb-06 20:51

KongHL

1-Feb-06 20:51

How do i extract text from MS word? It would be better if the end user does not need to have microsoft office installed.

Re: Text extraction

hsdok1-Feb-06 21:32

hsdok

1-Feb-06 21:32

The words from .doc file???

Re: Text extraction

James Gupta1-Feb-06 21:37

James Gupta

1-Feb-06 21:37

Well, try searching for any character with an ASCII value of between 32 and 128 (i think thats right, the characters that can be typed on a keyboard, but just check it before you do)

Re: Text extraction

toxcct1-Feb-06 22:06

toxcct

1-Feb-06 22:06

wrong, MS Word uses unicode...

TOXCCT >>> GEII power
[toxcct][VisualCalc 2.20][VCalc 3.0 soon...]

Re: Text extraction

KongHL1-Feb-06 21:54

KongHL

1-Feb-06 21:54

What i need is to convert a microsoft words document to a text file. How can I do this without having microsoft office? If not, using library in microsoft office is fine but how?

Re: Text extraction

Sebastian Schneider1-Feb-06 22:08

Sebastian Schneider

1-Feb-06 22:08

Geez. Open the document, parse it, but discard any formatting information - just keep the text. Write the text to a file. Done.

WHY, do YOU think, "Office-to-anything-else" converters are so freaking expensive?

Cheers,
Sebastian

--
Contra vim mortem non est medicamen in hortem.

Re: Text extraction

KongHL1-Feb-06 22:13

KongHL

1-Feb-06 22:13

how do i parse it?

Re: Text extraction

Sebastian Schneider1-Feb-06 22:18

Sebastian Schneider

1-Feb-06 22:18

From now on, questions are answered at a rate of 40 EUR/h.

Answering your last question would take around 6-12 months. Should I go ahead?

Seriously, if you really want to do it, you will have to analyze the file yourself. I aint got no clue how Word hides its content.

Cheers,
Sebastian

--
Contra vim mortem non est medicamen in hortem.

Re: Text extraction

grigsoft1-Feb-06 22:39

grigsoft

1-Feb-06 22:39

I could recommend www.wordcnv.com[^] - these guys have fastest library, which can be supplied in a small (<50K!) lib file, and their support is great. I'm using their library myself.

Igor Green
http://www.grigsoft.com/ - files and folders comparison tools

Re: Text extraction

Maximilien2-Feb-06 3:10

Maximilien

2-Feb-06 3:10

like others wrote, you need to do your own reverse engineering on the Word format to extract the text; which is no walk in the park.

I'm certain that if you google enough you might find something interresting on the subject.

Maximilien Lincourt
Your Head A Splode - Strong Bad

Re: Text extraction

David Crow2-Feb-06 5:03

David Crow

2-Feb-06 5:03

Without using Word, you'll need to know the format of a .doc file. See http://www.wotsit.org/[^] for this.

"The greatest good you can do for another is not just to share your riches but to reveal to him his own." - Benjamin Disraeli

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