C / C++ / MFC

Edit Box and the Enter/Return Key

25-May-04 5:39

What are you expecting to be displayed? The first cout statement will print the 0xff character but you'll not be able to see it as it's whitespace. The other two cout statements should print nothing.

"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

Re: Using memcpy

act_x25-May-04 5:47

act_x

25-May-04 5:47

#include "iostream.h"
#include"memory.h"
typedef unsigned char BYTE;

void main()
{
BYTE a[3]="\x42\x41";

cout<

Lint with MFC

act_x25-May-04 5:22

act_x

25-May-04 5:22

I am trying to use PC-Lint with an MFC app and am getting way too many messages where it is searching for some keywords. I would like to know if someone has got a quick start to this .
I added some additional options for a template from Scott Myers . I advised me to make some function parameters const . additionally , most of my functions do not modify data , so should i make them const ? What is the advantage of making a function const ? Apart from the fact that no one could use the function to modify existing data !

Re: Lint with MFC

Joe Woodbury25-May-04 6:32

Joe Woodbury

25-May-04 6:32

I stopped using PC-Lint about six months ago when it flagged perfectly good code and ignore a glaring errors, sometimes in the same file. It's a shame; it used to be a good program.

Incidentally, making a paramater or function const is an additional error check. It also reminds the developer that the class or parameter won't change; if it did, in some cases you would have to double buffer and item or ensure a string had sufficent memory allocated to it, etc.

The compiler can also use const to do some optimizations.

Anyone who thinks he has a better idea of what's good for people than people do is a swine.
- P.J. O'Rourke

sweep12325-May-04 4:55

25-May-04 4:55

I have a edit box which when I set the focus will allow the user to enter text. But when the
Enter or Return key is pressed the program terminates.

I have set the property to Want Return.

I am using the event OnEnChangeEdit1 to move the text and clear down the edit box when
the data entry cycle is complete.

How do you stop the Enter/Return key terminating the program?

Andrew Quinn AUS25-May-04 5:05

Andrew Quinn AUS

25-May-04 5:05

Hi,

Sounds like you have a dialog with the OK button as BS_DEFPUSHBUTTON style.

You can use the PreTranslateMessage virtual function to do whatever it is you want to do, e.g.

BOOL CMyDlg::PreTranslateMessage(MSG* pMsg)
{	
	BOOL bEatMsg = FALSE;
	if (pMsg && pMsg->message == WM_KEYDOWN)
	{
		// is this our editbox?
		if (pMsg->hwnd == m_ctrlEditBox.GetSafeHwnd())
		{
			// yes.. what was the key pressed?
			switch (pMsg->wParam)
			{
			case 13: // Enter
				// Do what you need to do...
				bEatMsg = TRUE;
				break;
			}
		}
	}
	return bEatMsg?TRUE:CDialog::PreTranslateMessage(pMsg);
}

Hope this helps,
Andy

sweep12325-May-04 5:58

25-May-04 5:58

Thanks Andy that worked a treat.

David Crow25-May-04 5:43

25-May-04 5:43

sweep123 wrote:
I have a edit box which when I set the focus will allow the user to enter text. But when the
Enter or Return key is pressed the program terminates.

I have set the property to Want Return.

Is the ES_MULTILINE style also being used?

sweep123 wrote:
How do you stop the Enter/Return key terminating the program?

Read here.

"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

sweep12325-May-04 6:42

25-May-04 6:42

The Multi-line was set to false.

If set that to true would that have sorted out the problem?

David Crow25-May-04 8:25

25-May-04 8:25

sweep123 wrote:
If set that to true would that have sorted out the problem?

That's ultimately up to you to determine. All I can do is suggest what the docs indicate, namely that when a multiline edit control is in a dialog box, the default response to pressing the ENTER key is to activate the default button. To use the ENTER key as a carriage return, use the ES_WANTRETURN style.

"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

sweep12325-May-04 21:34

25-May-04 21:34

Thanks for the info.

One effect I have with the use of the Edit Box is that if the user presses the Tab key when the Edit Box has focus then that is taken as an Enter key press.
This is with the Tabstop set to both true or false.

Note I set the Edit Box to read only until data input is expected, then its set to false and back again to true following the data entry.

David Crow26-May-04 2:16

Re: MACRO vs INLINE FUNCTION

26-May-04 2:16

sweep123 wrote:
One effect I have with the use of the Edit Box is that if the user presses the Tab key when the Edit Box has focus then that is taken as an Enter key press.
This is with the Tabstop set to both true or false.

This is not normal (i.e., default) behavior, unless you are doing something special with the VK_TAB key.

"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)

MACRO vs INLINE FUNCTION

avenger_sb2525-May-04 4:48

avenger_sb25

25-May-04 4:48

Hi geeks,

Please tell me when to use a MACRO and when to use an INLINE FUNCTION in C++. If this question has been asked before, please point me to that link.

I need an answer comparing the two. Please dont post definitions of macro and inline function as i am aware of them. Please give the answer in terms of efficiency, speed, code-size, pre-compilation/post-compilation, and things like that.
And please give examples ... Rose | [Rose]

...Avenger

Remember... testing & debugging are always part of programming ...so exterminate those stinking bugs

Maximilien25-May-04 4:53

Maximilien

25-May-04 4:53

always use inline ( or ordinary methods ).

the only reason I can give is that macros are preprocessor stuff and are not "debuggable"

Maximilien Lincourt
Your Head A Splode - Strong Bad

Re: MACRO vs INLINE FUNCTION

David Crow25-May-04 5:48