Re: value_type of vector - C / C++ / MFC Discussion Boards

Sanjay8899918-Nov-07 17:21

18-Nov-07 17:21

Hi,

I would like to know the difference between Regular DLL using shared MFC DLL, MFC extension DLL, Regular DLL with MFC statically linked. Which one is better in performance and all other important aspects. I would be thankful for ur help.

Thanks & Regards
Sanjay S. Umap

Re: MFC DLL

Paresh Chitte18-Nov-07 17:54

Paresh Chitte

18-Nov-07 17:54

Please start from,

http://www.codeguru.com/cpp/cpp/cpp_mfc/tutorials/article.php/c4017/[^]
http://www.codeguru.com/cpp/cpp/cpp_mfc/tutorials/article.php/c4019/[^].

Regards,
Paresh.

Socket Error

manish.patel18-Nov-07 16:15

manish.patel

18-Nov-07 16:15

Hello All,

In Socket Programing i am getting an Error No 10053.
It is for Connection closed by Software.

So anybody Tell me what is the problem inside?

Thanks in Advance.

Manish Patel.
B.E. - Information Technology.

Re: Socket Error

Mark Salsbery18-Nov-07 16:21

Mark Salsbery

18-Nov-07 16:21

What's going on in the code when you get the error?

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Re: Socket Error

manish.patel18-Nov-07 16:32

manish.patel

18-Nov-07 16:32

At client side connection get close.

But server at server after that it cannot send messages.

Thanks and Regards,
Manish Patel.
B.E. - Information Technology.

Re: Socket Error

Peter Weyzen18-Nov-07 19:29

Peter Weyzen

18-Nov-07 19:29

10053 referred to as ECONNABORTED or WSAECONNABORTED.

The TCP stack on your computer has decided to terminate the connection because something BAD happened in it's conversation with the host.

The error is kinda mysterious, and doesn't point to a cause. And the cause could either either side of the connection -- you or the host.

See this link for a description of the error: http://www.sockets.com/err_lst1.htm#WSAECONNABORTED[^]

If your server is developed in-house -- go talk to them. It could be their fault -- possibly either software or server configuration or even a routing problem.

If not, go visit their website. You are probably not the first to run into this problem.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~<br />
Peter Weyzen<br />
Staff Engineer<br />
<A HREF="http://www.soonr.com">SoonR Inc -- PC Power delivered to your phone</A>

value_type of vector

George_George18-Nov-07 16:07

George_George

18-Nov-07 16:07

Hello everyone,

I think the value_type of vector<int> should be int and the value_type of vector<int> should be int*. But I am not 100% sure,

1. how to write a program to verify this idea;
2. where to find the definition that the value_type of interator of vector<int> is int*.

It is appreciated if you could help.

<br />
#include <vector><br />
<br />
using namespace std;<br />
<br />
int main (int argc, char** argv)<br />
{<br />
	vector<int>::value_type;  // should be int ?<br />
	vector<int>::iterator::value_type; // should be int* ?<br />
<br />
	return 0;<br />
}<br />

thanks in advance,
George

Re: value_type of vector

Stephen Hewitt18-Nov-07 18:00

Stephen Hewitt

18-Nov-07 18:00

Firstly we can't see the “<” and “>” characters in your post or what’s between them – this information is vital if you expect an answer to your post. Do you review your posts?

I assume you mean the following:

#include <vector>
 
using namespace std;
 
int main (int argc, char** argv)
{
vector<int>::value_type; // should be int ?
vector<int>::iterator::value_type; // should be int* ?
 
return 0;
}

The line vector<int>::iterator::value_type is incorrect and might result in compiler errors (depending on the particular STL implementation you’re using.) The correct way to get type information is as follows:

#include <vector>
#include <iterator>
// …Other stuff…
iterator_traits<vector<int>::iterator>::value_type
// …Other stuff…

The reason for using external adaptation via the iterator_traits class is simple: it allows the use of types such as int* to be used as iterators (since int*s are not classes and so can’t expose a value_type directly.) Also note that the crap-fest STL that comes with MSVC6 will fail to compile the code I gave because it’s missing the required iterator_traits specializations.

Also note that you can not assume that an iterator is a pointer: it may or may not be depending on many factors, among them the whims of the implementors (of the STL being used.)

Steve

Re: value_type of vector

George_George18-Nov-07 19:46

George_George

18-Nov-07 19:46

Thanks Steve!

I have also referred some links, like this one in sgi implementation,

http://www.sgi.com/tech/stl/iterator_traits.html[^]

Currently, I am using Visual Studio 2005 and using other implementation to illustrate is also fine. Yes, you are correct, I mean vector with greater than and less than signs.

From your reply, I do not understand why from this statement,

iterator_traits<vector<int>::iterator>::value_type

if the type of vector is T or int (i.e. vector <t> or vector <int>), the value_type iterator is also defined to T or int? How it is implemented? For example, from either sgi implementation or Visual Stuido 2005 implementation is fine.

regards,
George

Re: value_type of vector

Stephen Hewitt18-Nov-07 20:01

Stephen Hewitt

18-Nov-07 20:01

In <iterator> (or some implementation defined file included by it) you'll find a template something like this:

template <class Iterator>
struct iterator_traits
{
	typedef typename Iterator::iterator_category iterator_category;
	typedef typename Iterator::value_type        value_type;
	typedef typename Iterator::difference_type   difference_type;
	typedef typename Iterator::pointer           pointer;
	typedef typename Iterator::reference         reference;
};

This simply forwards the requests to the iterator class. The following partial specialization allows would allow pointers to be used as iterators (note that MSVC6 can’t handle partial template specialization):

template <class T>
struct iterator_traits<T*>
{
	typedef random_access_iterator_tag iterator_category;
	typedef T                          value_type;
	typedef ptrdiff_t                  difference_type;
	typedef T*                         pointer;
	typedef T&                         reference;
};

Note that no forwarding is used here: the types are defined in-place.

Steve

Re: value_type of vector

George_George18-Nov-07 20:47

George_George

18-Nov-07 20:47

Thanks Steve,

I have read through the above codes, but I am confused that when the statement as you mentioned,

<code>
iterator_traits<vector<int>::iterator>::value_type
</code>

whether

<code>
template <class Iterator>struct iterator_traits
</code>

or

<code>
template <class T>struct iterator_traits<T*>
</code>

is invoked?

regards,
George

Re: value_type of vector

Stephen Hewitt19-Nov-07 12:38

Stephen Hewitt

19-Nov-07 12:38

Looks like you need to check out Partial template specialization[^].

Steve

Re: value_type of vector

George_George19-Nov-07 15:38

George_George

19-Nov-07 15:38

Thanks Steve,

My question is answered.

regards,
George

CFileDialog can not been closed while it owner been closed.

CooperWu18-Nov-07 15:51

CooperWu

18-Nov-07 15:51

My project contains client application and server application. Always using server to control the client side. A Dialog at client side using a CFileDialog to open a image file. the problem is, after the server side close client side dialog, but the CFileDialog remains on screen.

We tried lots of way to close CFileDialog, but failed.
like EndDialog(), EndModalLoop(IDCANCEL) EndModalLoop(IDOK), and PostMessage(WM_KEYDOWN,VK_ESCAPE, 0)

So....what can I try next?
--

I create a demo to show this problem. Dialog A calls Dialog B, and Dialog B calls a CFileDialog, then add timer event in Dialog A to Destroy Dialog B. the CFileDialog was closed too.
Does this demo wrong to reproduce this problem?

Re: CFileDialog can not been closed while it owner been closed.

Nishad S18-Nov-07 16:41

Nishad S

18-Nov-07 16:41

You have probably not set the parent window of the CFileDialog.

- NS -
[ODBaseBtn]

Re: CFileDialog can not been closed while it owner been closed.

moye250118-Nov-07 17:35

moye2501

18-Nov-07 17:35

Thanks for your reply. I tried set fFileDlg.m_pOFN->hwndOwner = this->GetParent()->m_hwnd, but it's doesn't work. Cry | :((

-- WuJunyin

Re: CFileDialog can not been closed while it owner been closed.

Nishad S18-Nov-07 19:32

Nishad S

18-Nov-07 19:32

Can you show me the code fragment regarding this?

- NS -
[ODBaseBtn]

Re: CFileDialog can not been closed while it owner been closed.

CooperWu18-Nov-07 20:08

CooperWu

18-Nov-07 20:08

<br />
CString strFilter = "...";    <br />
CFileDialog fFileDlg(TRUE,NULL,NULL,OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT,strFilter,NULL);<br />
fFileDlg.m_pOFN->hwndOwner = this->GetParent()->m_hwnd;<br />
<br />
if (fFileDlg.DoModal() == IDOK)<br />
{<br />
  ...<br />
}<br />

Re: CFileDialog can not been closed while it owner been closed.

Nishad S18-Nov-07 21:14

Nishad S

18-Nov-07 21:14

Try like this...

CFileDialog fFileDlg(TRUE,NULL,NULL,OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT,strFilter,this);
//fFileDlg.m_pOFN->hwndOwner = this->GetParent()->m_hwnd;
if (fFileDlg.DoModal() == IDOK)

- NS -
[ODBaseBtn]

Re: CFileDialog can not been closed while it owner been closed.

CooperWu18-Nov-07 21:21

CooperWu

18-Nov-07 21:21

I have tried it before I post this message. Poke tongue | ;-P