C / C++ / MFC Discussion Boards

Non display characters for selection count

ForNow8-Mar-16 19:44

8-Mar-16 19:44

Hi

I have 3 rows of text in my rich edit.
At the end of each line I move a carriage return line feed, to force a new line
/r/n. Do these 2 bytes count as 2 characters when determining the count for the selection

Thanks

Re: Non display characters for selection count

Richard MacCutchan8-Mar-16 21:45

Richard MacCutchan

8-Mar-16 21:45

The documentation at EM_GETSELTEXT message (Windows)[^] does not explicitly say whether it does, or does not. But a simple test should prove it one way or another.

Re: Non display characters for selection count

ForNow9-Mar-16 3:55

ForNow

9-Mar-16 3:55

cr/lf 0X0D0A is treated as 1 character for rich edit purposes

thanks

Re: Non display characters for selection count

David Crow9-Mar-16 4:24

David Crow

9-Mar-16 4:24

Really? I just tested (using VS2008) and it came out as two separate characters. Here's the code I used:

// the control contained the text: David\r\n

void CMyDialog::OnClickedOk()
{
    int len = m_richedit.GetWindowTextLength();
    TRACE(_T("Len = %d\n"), len);

    CString text;
    m_richedit.GetWindowText(text);
    TRACE(_T("Text = %s\n"), text);

    for (int x = 0; x < len; x++)
        TRACE(_T("%#x\n"), text[x]);
}

The resulting output looked like:

Len = 7
Text = David

0x44
0x61
0x76
0x69
0x64
0xd
0xa

"One man's wage rise is another man's price increase." - Harold Wilson

"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons

"You can easily judge the character of a man by how he treats those who can do nothing for him." - James D. Miles

Re: Non display characters for selection count

ForNow9-Mar-16 4:32

ForNow

9-Mar-16 4:32

I was referring to richedit when determining the selection position

Re: Non display characters for selection count

David Crow9-Mar-16 4:49

David Crow

9-Mar-16 4:49

So you are taking whatever text is already present in the edit control and adding CRLF to the end of it? I'm trying to ascertain if this is an appending issue (I've seen some weird ways in which folks try to append to an edit control) or something else.

modified 9-Mar-16 11:41am.

Re: Non display characters for selection count

ForNow9-Mar-16 4:58

ForNow

9-Mar-16 4:58

For Crlf which is 2 bytes in memory aka the buffer
I count 1 for determining the selection count

Re: Non display characters for selection count

David Crow9-Mar-16 5:03

David Crow

9-Mar-16 5:03

But are taking whatever text is already present in the edit control and adding CRLF to the end of it?

Re: Non display characters for selection count

ForNow9-Mar-16 5:20

ForNow

9-Mar-16 5:20

The text is included in the count for the cold I count as 1 character for porpouses of selection not 2 bytes

Re: Non display characters for selection count

David Crow9-Mar-16 5:40

David Crow

9-Mar-16 5:40

I misunderstood what you were attempting.

You are using the GetSel() method to get the starting and ending positions of the control's selected text, correct? I tried that and with all of the text in the control selected, I found that CR and LF are (like I would expect) considered two separate characters. In other words, start = 0 and end = 7.

Re: Non display characters for selection count

ForNow9-Mar-16 5:45

ForNow

9-Mar-16 5:45

I use the Streamout api to get whatever is in the control the edit control has 4 lines at the end of each line is X0D0A CRLF I have to count the 0X0D0A as 1 character for the SetSel api when determining the pos I want to use in the selection

thanks

Re: Non display characters for selection count

David Crow9-Mar-16 5:53

David Crow

9-Mar-16 5:53

So your end game is just to programmatically insert/replace some characters some place in the edit control?

modified 9-Mar-16 12:22pm.

Re: Non display characters for selection count

ForNow9-Mar-16 6:21

ForNow

9-Mar-16 6:21

I have 16 pieces of text in the 4 line edit control any one of whom I could potentially replace

Re: Non display characters for selection count

Richard MacCutchan9-Mar-16 6:18

Richard MacCutchan

9-Mar-16 6:18

I just tried this with an ordinary Edit control, and it returns both CR LF in the count.

Re: Non display characters for selection count

Bram van Kampen9-Mar-16 14:52

Bram van Kampen

9-Mar-16 14:52

You did not try this in a Multi Threaded Environment, as explained in the question previous of this
Smile | :)

Bram van Kampen

Re: Non display characters for selection count

Richard MacCutchan9-Mar-16 22:11

Richard MacCutchan

9-Mar-16 22:11

Sorry, but I am not sure what relevance that has to the counting of characters.

Re: Non display characters for selection count

Bram van Kampen9-Mar-16 14:49

Bram van Kampen

9-Mar-16 14:49

Well,
This is Familiar, in particular with the multi threaded question you asked earlier.

MFC cannot realy handle multiple threads. No one seems to know why, I have asked the question before.

At any rate, the only way MFC objects can communicate between threads is with the Old Fashioned WDK Kernel Function ::SendMessage(hWnd, Param1,Param2);
In MFC you create your Message as WM_USER+(X), Create a Message Handler, and, manually add it to the message map.

Any attempt to call an MFC Object from a different thread than in which it was created always ultimately lead to failure.
The Symptoms are: Works, Add a Virtual Function: It stops Working

Hope this helps

Bram van Kampen

modified 9-Mar-16 21:08pm.

Re: Non display characters for selection count

Richard MacCutchan9-Mar-16 22:11

Richard MacCutchan

9-Mar-16 22:11

... and I don't think you meant to post this message to me.

Re: Non display characters for selection count

Bram van Kampen10-Mar-16 14:19

Bram van Kampen

10-Mar-16 14:19

Sorry Richard,
No I Did Not intend this for you.
This topic became a Sort of a Labyrinth.

The Original Person is evidently out of his/her depth! (S)he is still hammering the subject I see.
I try to help, as we all do, but can get frustrated when good advise is ignored, as, I am sure you do to.

Regards,

Bram. Frown | :(

Bram van Kampen

Re: Non display characters for selection count

David Crow10-Mar-16 2:48

David Crow

10-Mar-16 2:48

Relevance? Confused | :confused:

Re: Non display characters for selection count

leon de boer15-Mar-16 20:22

leon de boer

15-Mar-16 20:22

EM_GETSELTEXT is explicit

This message returns the number of characters copied, not including the terminating null character.

The call is terminated by the null character and if you have CR,LF they will count as characters
The return is a CHARACTER COUNT, if your edit box is unicode mode it still reflects the character NOT THE NUMBER OF BYTES.

Hence when providing a buffer you are best to use an array of TCHAR rather than a standard byte array to allow for size difference.

Also note when size a TCHAR array use _countof DO NOT use sizeof for the same reason. Standard unicode aware coding practice.

Several of the comments have confusion between CHARACTER and BYTE within the meaning of the windows API. No such confusion exists.

In vino veritas

modified 16-Mar-16 2:46am.

confused in static member function of class.

Member 87269408-Mar-16 19:01

Member 8726940

8-Mar-16 19:01

hello,
I had a confusion that why we can use :: sign in calling static member function of class.
while in the case of calling simple member function using :: sign shows error .. in c++.
Please explain .

Re: confused in static member function of class.

Richard MacCutchan8-Mar-16 21:37

Richard MacCutchan

8-Mar-16 21:37

Member functions need qualifiers in order for the compiler to know which function your code refers to. In the case of a static function the qualifer must be the class name, since static functions belong to the class: hence Class::Function(). For member functions the qualifer must be the instance reference, as non-static functions are attached to individual objects: hence object.Function() or objectpointer->Function().

Re: confused in static member function of class.

Member 872694014-Mar-16 19:19

Member 8726940

14-Mar-16 19:19

thank you so much for clearing my doubt

Assertion failure While Editing CTreeView Label.

shanmugarajaa8-Mar-16 9:04

shanmugarajaa

8-Mar-16 9:04

Dear Friend,

After adding all necessary message handler to support to edit label in CTreeView

void CMyTreeView::OnBeginLabelEdit( NMHDR* /*pNMHDR*/, LRESULT* pResult)
{
	// This is the Limit the size of the Tag Name to 127
	CTreeCtrl &ctlFiles = GetTreeCtrl();
	ctlFiles.GetEditControl()->LimitText( 127 );
	*pResult = 0;
}

void CMyTreeView::OnEndLabelEdit( NMHDR * pNMHDR, LRESULT *  pResult )
{
	*pResult = TRUE;
}

BOOL CMyTreeView::PreTranslateMessage(MSG* pMsg)
{

	if ( pMsg->message == WM_KEYDOWN )
	{
		CTreeCtrl &ctlFiles = GetTreeCtrl();
		CEdit* edit = ctlFiles.GetEditControl();
		if (edit)
		{
			if( GetKeyState( VK_CONTROL ) && pMsg->wParam == VK_C )
			{
				edit->Copy();
				return TRUE;
			}
			if( GetKeyState( VK_CONTROL ) && pMsg->wParam == VK_V )
			{
				edit->Paste();
				return TRUE;
			}
			if( GetKeyState( VK_CONTROL ) && pMsg->wParam == VK_X )
			{
				edit->Cut();
				return TRUE;
			}
			if( GetKeyState( VK_CONTROL ) && pMsg->wParam == VK_Z )
			{
				edit->Undo();
				return TRUE;
			}
			if( pMsg->wParam == VK_RETURN || pMsg->wParam == VK_ESCAPE || pMsg->wParam == VK_CONTROL || pMsg->wParam == VK_INSERT )
			{
				edit->SendMessage(WM_KEYDOWN, pMsg->wParam, pMsg->lParam);
				return TRUE;
			}
		}
	}
	return CTreeView::PreTranslateMessage(pMsg);
}

If I press a character 'a' to 'z' and 'A' to 'z' then MFC throwing Assertion.

I don't know what I am missing out to avoid this issue.
Kindly help me on this.

Thanks,
S Shanmuga Raja

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.