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From: dixon@sagittarius.crd.ge.com (walt dixon)
Newsgroups: comp.windows.ms.programmer
Subject: edit controls containing floating point numbers
Message-ID: <18368@crdgw1.crd.ge.com>
Date: 9 Apr 91 17:37:45 GMT
Sender: news@crdgw1.crd.ge.com
Reply-To: dixon@crd.ge.com (walt dixon)
Organization: General Electric Corp. R&D, Schenectady, NY
Lines: 41

I am in the process of writing my first serious windows application.
This program works with floating point numbers and occasionally must
accept input/display output in a dialog box.  I seem to be standing
on my head to work with floating point numbers,  so I am appealing
to the collective wisdom of the net for a better solution.

I am currently working with a small memory model and explicitly
naming text segments.  I have written far procedures that call
relevant library routines,  ie

char * far lib_gcvt(...)
{
  gcvt(...)
}

These interface procedures are in the default TEXT segment so
there are no problems using the small model libraries.  I'm using
this technique so I don't clutter up my TEXT segment with a lot
of dialog procedures.  I reasoned that the conversions were complex
enough and called infrequently enough that the extra call overhead
is insignificant.  This approach seems reasonable.

Where I am having difficulty is detecting invalid numbers.  My
current solution is to subclass the edit controls.  Whenever
one of these controls looses input focus,  I retrieve the text string
and try to do a floating point conversion.  If the conversion fails,
I beep and reset focus.  

I know there are some problems with this approach.  Does anyone have
any suggestions?  Please respond direcly to me and I will post a
summary.

Thanks

Walt Dixon      {internet:      dixon@crd.ge.com        }
                {us mail:       ge-crd                  }
                {               po box 8                }
                {               schenectady, ny 12301   }
                {phone:         518-387-5798 (W)        }
                {               518-875-6203 (H)        }
Walt Dixon dixon@crd.ge.com