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Re: How to Pass variable name to a function

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Andreas Bergmaier wrote:
> 
> Stan Weiss schrieb:
> > save(stanForm.VD.value, AInput, 'Valve Diameter')"
> >
> > function save( field, vary, text ) {
> >       if( isNaN( field ) )
> >       {
> >          alert( text + " is not numeric" );
> >       }
> >       else
> >       {
> >           AInput = eval(field);  // this Works
> >           vary = eval(field);    // this does not workWorks
> >       }
> > }
> >
> > Can anyone see what I am doing wrong?
> 
> JavaScript does not have call-by-reference. Instead of passing a
> reference to the variable where the result should be stored, you pass
> the actual value of AInput to the function, where it gets the value of
> the local variable "vary". By assigning the result to vary, vary will
> get a new value. AInput is forgotten.
> 
> Also, you seem to try to parse a number with eval. Urghh. Use
> parseFloat() instead.
> 
> So, your code should be:
> 
> function numeric(field, fallback, name) {
>      var num = parseFloat(field);
>      if (isNaN(num)) {
>          alert(name + " is not numeric");
>          return fallback;
>      } else
>          return num;
> }
> AInput = numeric(stanForm.VD.value, AInput, 'Valve Diameter');
> 
> regards,
>   Bergi

Thanks for the reply Bergi. It now return the correct value but does not
function the way it did before. If a numeric and alpha are entered it
will take the numeric part and use it. I want it to show any error if
the field is not all numeric.

So I changed
      if (isNaN(num)) {
to
      if( isNaN( field ) )

Thanks again for your help
Best Regards
Stan

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Thread

How to Pass variable name to a function Stan Weiss <srweiss@erols.com> - 2012-04-11 12:26 -0400
  Re: How to Pass variable name to a function Andreas Bergmaier <andber93@web.de> - 2012-04-11 19:47 +0200
    Re: How to Pass variable name to a function Stan Weiss <srweiss@erols.com> - 2012-04-11 14:21 -0400
      Re: How to Pass variable name to a function Stefan Weiss <krewecherl@gmail.com> - 2012-04-11 20:53 +0200
        Re: How to Pass variable name to a function Stan Weiss <srweiss@erols.com> - 2012-04-11 15:16 -0400
          Re: How to Pass variable name to a function Gene Wirchenko <genew@ocis.net> - 2012-04-11 15:18 -0700
  Re: How to Pass variable name to a function "Evertjan." <exjxw.hannivoort@interxnl.net> - 2012-04-11 21:20 +0000
  Re: How to Pass variable name to a function Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2012-04-11 23:56 +0200
    Re: How to Pass variable name to a function Stan Weiss <srweiss@erols.com> - 2012-04-12 00:48 -0400
      Re: How to Pass variable name to a function Andrew Poulos <ap_prog@hotmail.com> - 2012-04-12 15:21 +1000
        Re: How to Pass variable name to a function Stan Weiss <srweiss@erols.com> - 2012-04-12 02:11 -0400
          Re: How to Pass variable name to a function Andrew Poulos <ap_prog@hotmail.com> - 2012-04-12 18:57 +1000
            Re: How to Pass variable name to a function Stan Weiss <srweiss@erols.com> - 2012-04-12 09:35 -0400
      Re: How to Pass variable name to a function Stefan Weiss <krewecherl@gmail.com> - 2012-04-12 08:08 +0200
        Re: How to Pass variable name to a function Stan Weiss <srweiss@erols.com> - 2012-04-12 10:13 -0400
      Re: How to Pass variable name to a function Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2012-04-12 22:47 +0200
        Re: How to Pass variable name to a function Stan Weiss <srweiss@erols.com> - 2012-04-12 17:04 -0400
          Re: How to Pass variable name to a function Tim Streater <timstreater@greenbee.net> - 2012-04-12 22:17 +0100
          Re: How to Pass variable name to a function Scott Sauyet <scott.sauyet@gmail.com> - 2012-04-13 05:13 -0700
            Re: How to Pass variable name to a function "Evertjan." <exjxw.hannivoort@interxnl.net> - 2012-04-13 16:27 +0000
              Re: How to Pass variable name to a function Scott Sauyet <scott.sauyet@gmail.com> - 2012-04-16 04:11 -0700
        Re: How to Pass variable name to a function "Tom de Neef" <tdeneef@qolor.nl> - 2012-04-12 23:34 +0200
          Re: How to Pass variable name to a function Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2012-04-13 10:03 +0200
          Re: How to Pass variable name to a function Erwin Moller <erwinmollerusenet@xs4all.nl> - 2012-04-13 12:03 +0200
            Re: How to Pass variable name to a function Andrew Poulos <ap_prog@hotmail.com> - 2012-04-13 21:35 +1000
            Re: How to Pass variable name to a function Gene Wirchenko <genew@ocis.net> - 2012-04-13 09:00 -0700
  Re: How to Pass variable name to a function Stan Weiss <srweiss@erols.com> - 2012-04-12 14:03 -0400
  Re: How to Pass variable name to a function Dr J R Stockton <reply1215@merlyn.demon.co.uk.not.invalid> - 2012-04-12 20:06 +0100
    Re: How to Pass variable name to a function Stan Weiss <srweiss@erols.com> - 2012-04-12 18:54 -0400

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