C / C++ / MFC

5-May-02 11:05

Thank you

James R. Twine6-May-02 3:12

James R. Twine

6-May-02 3:12

Tom Archer wrote:
szReversed = _strrev(str.GetBuffer(0));

The OP may have to call ReleaseBuffer(...) after reversing the string if the CString itself continues to be used... Of course, at this point szReversed should be treated as a const pointer...

Peace!

-=- James.
(Try Check Favorites Sometime!)

Tom Archer6-May-02 3:20

Tom Archer

6-May-02 3:20

Good point, James. I omitted mentioning the CString::ReleaseBuffer in this example because I assumed that the CString would not be used any further. I should probably include a sentence about using the CString::ReleaseBuffer when prescribing the CString::GetBuffer function.

Cheers,
Tom Archer
Author - Inside C#, Visual C++.NET Bible

A total abstainer is one who abstains from everything but abstention, and especially from inactivity in the af

KarstenK6-May-02 3:43

KarstenK

6-May-02 3:43

You should ReleaseBuffer call after you´re ready with the szReversed!!!
While you´re poiting to the CString buffer it should be locked.;)

James R. Twine6-May-02 4:03

James R. Twine

6-May-02 4:03

KarstenK wrote:
You should ReleaseBuffer call after you´re ready with the szReversed!!!
While you´re poiting to the CString buffer it should be locked.

   While you are manipulating the buffer, the buffer should be locked.  And, from the OP's original question: "I am trying to use string reverse (_strrev) function to reverse a string", so (s)he is done with manipulating szReversed after the contents have been reversed.

   The problem is that if the OP tried to append to the CString right after the call to ::strrev(...), the reversed CString would likely be lost.  But not if CString::ReleaseBuffer(...) had been called.

   " Smile | :)

"

Peace!

-=- James.
"Fat people are hard to kidnap."
(Try Check Favorites Sometime!)

One more CListBox question

KarstenK6-May-02 4:12

KarstenK

6-May-02 4:12

It seems to be so easy to use in this case "CString::MakeReverse()" that I tought there should be some tricky stuff. Confused | :confused:

tordyvel5-May-02 9:34

Re: One more CListBox question

5-May-02 9:34

How do you delete all items in a CListBox object?

Jack Handy5-May-02 10:29

Jack Handy

5-May-02 10:29

I believe you are looking for MyListBox.ResetContent();

-Jack

To an optimist the glass is half full.
To a pessimist the glass is half empty.
To a programmer the glass is twice as big as it needs to be.

Re: One more CListBox question

tordyvel5-May-02 10:30

Sort help with Visual C++

5-May-02 10:30

Yes that's the one Smile | :)

Thanks!

Learning5-May-02 9:24

5-May-02 9:24

I need some help with sort function in Visual C++.

Here is the situation :

I have a variable "m_strEditData" whose type is CString. I want to sort the string and move the data to another CString "m_strResultData".

I want this to be an inline code and not called as a function. Can anyone help me with this?
Greatly appreciated.
M

Joaquín M López Muñoz5-May-02 9:39

Joaquín M López Muñoz

5-May-02 9:39

Do you mean sorting the characters your string is composed of? If so, this should do:

#include <algorithm>
...
m_strResultData=m_strEditData;
int nLength=m_strResultData.GetLength();
LPSTR buffer=m_strResultData.GetBuffer(nLength);
std::sort(buffer,buffer+nLength);
m_strResultData.ReleaseBuffer();

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Learning5-May-02 10:29

5-May-02 10:29

Thank you.

The Sort worked but as I was testing I rank into a situation (explained below). Is there a way to solve it.
Input data---> acbde
After sort function---> abcde
This is fine. But if I enter in input data
Input data----> This is my dog
Output ===> Sort all the characters together.
Is there a way to just sort only on the first character.
The result of my example after the sort would be :
"dog is my This".

Is this easily possible?
Thank you
M

Joaquín M López Muñoz5-May-02 11:04

Joaquín M López Muñoz

5-May-02 11:04

This can be done, but involves a little more work. Here's an outline of the method:

#include <algorithm>
#include <sstream>
#include <string>
#include <vector>
...
// split into words and store them in a vector.
std::vector<std::string> v;
std::istringstream istr((LPCSTR)m_strEnterData);
for(;;){
  std::string s;
  istr>>s;
  if(s.empty())break;
  v.push_back(s);
}
// sort the words
std::sort(v.begin(),v.end());
// output the result to m_strDisplayResult
m_strDisplayResult="";
for(std::vector<std::string>::const_iterator it=v.begin();
    it!=v.end();
    ++it){
  if(it!=v.begin())m_strDisplayResult+=" ";
  m_strDisplayResult+=it->c_str();
}

(Sort of, I haven't compiled this.)

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Learning5-May-02 11:42

5-May-02 11:42

Thank you. I am going to review it and try to understand it.
I am not familiar with Vector operation but I am excited about learning it. I have a book. I will read more and will let you know.

Thank you
M

Joaquín M López Muñoz5-May-02 12:00

Joaquín M López Muñoz

5-May-02 12:00

Thank you. I am going to review it and try to understand it.

I'm glad you decided to do so. STL can help you be more productive and write more robust code. Usually, trying to do this kind of things by hand results in off-by-one errors and mistakes like that.
In case you're interested, Christian Grauss has written several tutorials on different aspects of STL. Check them out at the STL section here at CodeProject. Good luck!

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Joaquín, Thank you...EOM

Learning6-May-02 1:46

6-May-02 1:46

Thank you

CListBox

tordyvel5-May-02 9:00

5-May-02 9:00

Which function in CListBox returns the selected items textstring? Confused | :confused:

Re: CListBox

alex.barylski5-May-02 9:12

alex.barylski

5-May-02 9:12

CString buff;

GetText(GetCurSel(), buff);

GetSelCount(); will return the number of selected items in a listbox if it's a multi-selection enabled.

"An expert is someone who has made all the mistakes in his or her field" - Niels Bohr

Re: CListBox

tordyvel5-May-02 9:15