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How to get to protected member m_nIDHelp

Medium Priority
Last Modified: 2013-11-20
There is a protected member variable m_nIDHelp.  I am
not sure if it is a member of the CWnd class or the
CDialog class.  It shows up as a "protected" member
of my CDialog object in the debugger.

Anyway, the question is, is there an access function
available so that I can get to this from outside the
class?  Or am I going to have to subclass from CDialog
and provide my own access function?

By the way, what do I do when an expert answers a
question that is not sufficient?  My question is tagged
as answered and waiting for a grade so no one looks
at it.  The expert said to get back to him if it was
not sufficient, but the only way I have to do this is
by posting a comment and I have had no response for
quite a while.  The first response was virtually
immediate, but now it sits.
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In afxwin.h you find the definition of CDialog, included the member:
        UINT m_nIDHelp;
There you also find:
      void SetHelpID(UINT nIDR);
You can call this member from outside the class.

By the way, if you do not agree with someone's answer, do the following: When you evaluate the proposed answer, use the radio button with the lowest agreement (I don't know the correct text, but when it says "excellent-good-ok-bad", use bad). The question then does not loose the status of a question; it will be put back to the unanswered questions.

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Thank you for resonding.  I did see the definition of CDialog in afxwin.h and the void SetHelpID(UNIT nIDR) function.  However, I need to be able to retrieve the value, not set it.

I assume this means that I will have to provide this myself.

Also, thank you for your advice about question status.
you also find in the MFC-sources:

 if (m_nIDHelp != 0)
  return HID_BASE_RESOURCE + m_nIDHelp;
 return 0;

I think you can use this member to retrieve your actual m_nIDHelp with:
  UINT helpId = myDialog->SendMessage(WM_HELPHITTEST);
  if( helpId ) helpId -= HID_BASE_RESOURCE;
This should work!


I tried it and have not yet been able to get it to work.
It is necessary to include afxpriv.h, but I get many compilation errors in it when I do so.  I assume that it requires yet another header, but I have not yet found it.  Thank you.  I will let you know when I get it.


As I indicated in my last comment, I have not been able to get
UINT helpId = myDialog->SendMessage(WM_HELPHITTEST);
if( helpId ) helpId -= HID_BASE_RESOURCE;
to work when including afxpriv.h.  I do not know how to elimination the multitude of compilation errors that occur when including that file.  I tried defining WM_HELPHITTEST and HID_BASE_RESOURCE myself to the value in afxpriv.h
#define WM_HELPHITTEST      0x0366
#define HID_BASE_RESOURCE   0x00020000UL  
which did work.  However, this is a embarassing work around.  Do you have any ideas, what the problem is.  Do I need to include yet another file?

I use VC++ 5.0 and do not have any problems with it.
I just built up a little example, and I can send you the files with e-mail, if you tell me your email-adress
(send it to:  MarkusLoibl@ThinkTools.com )

I use VC++ 5.0 and do not have any problems with it.
I just built up a little example, and I can send you the files with e-mail, if you tell me your email-adress
(send it to:  MarkusLoibl@ThinkTools.com )

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