Solved

CDialog Class Member Variable precision

Posted on 1997-10-17
4
231 Views
Last Modified: 2013-11-20
How do I set the precision for the variables.  Similar to iostream.setprecision, Fortran "FIX" etc.  I would like not to convert back and forth between types.  Can't find this info in my books or the CD-ROM online help.  Thanks for any help in this "simple" matter.
0
Comment
Question by:lucie
  • 2
4 Comments
 
LVL 3

Expert Comment

by:shaig
ID: 1308360
I don't understand what do CDialog members have to do with precision, and if they do, could you be more presice?

Anyway this is probably a C/C++ question:
the copnversion between types in C is automatic.
It is possible to set the precision when:
a) printing - sprintf or CString::Format.  example:
  sprintf( buffer, "The float value is: %8.2f", m_floatVarible );
b) inputing - scanf(), very simulare.

hope i helped.  : - {}
0
 

Author Comment

by:lucie
ID: 1308361
VC++ uses DDX/DDV to exchange data between the Dialog Control and the Member Variable.  In context:

m_floatVariable = sqrt(some_value);

When variable data sent back to the Dialog Control, the Dialog Box displays a number like 4.23592347575, when I'd like to see a number 4.24 or 4.236.  I've found that I can accomplish this by changing the type from "double" using the _fcvt function which allows you to control the # of digits after the decimal.  I'd just like to control rounding of the variable without changing types.  In fortran, I'd just FIX 2 or 3 and be done with it.  Just want to know if you can do this in VC++
0
 
LVL 10

Accepted Solution

by:
RONSLOW earned 50 total points
ID: 1308362
Write your own DDX routine (copy the MFC version or at least call it) and do your percision fixes there.

something like this ...

void AFXAPI DDX_Text_2DP(CDataExchange* pDX, int nIDC, float& value)
{
      if (pDX->m_bSaveAndValidate) {
            DDX_Text(pDC,nIDC,value);
      } else {
            CString buffer;
            HWND hWndCtrl = pDX->PrepareEditCtrl(nIDC);
            buffer.Format("%.2f", value);
            ::SetWindowText(hWndCtrl, szBuffer);
      }
}

0
 

Author Comment

by:lucie
ID: 1308363
Thanks verrrrrrry much.

0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
function returning CString in a regular win32 DLL 8 161
VB.NET how to use the Vertical ScrollBar 5 90
maxBlock challenge 30 111
sumHeights2  challenge 7 87
Introduction: The undo support, implementing a stack. Continuing from the eigth article about sudoku.   We need a mechanism to keep track of the digits entered so as to implement an undo mechanism.  This should be a ‘Last In First Out’ collec…
Have you tried to learn about Unicode, UTF-8, and multibyte text encoding and all the articles are just too "academic" or too technical? This article aims to make the whole topic easy for just about anyone to understand.
This video will show you how to get GIT to work in Eclipse.   It will walk you through how to install the EGit plugin in eclipse and how to checkout an existing repository.
I designed this idea while studying technology in the classroom.  This is a semester long project.  Students are asked to take photographs on a specific topic which they find meaningful, it can be a place or situation such as travel or homelessness.…

948 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

23 Experts available now in Live!

Get 1:1 Help Now