"mitsubishi" <webforumsuser@macromedia.com> wrote in message
news:c284tb$f3d$1@forums.macromedia.com...
> This probably is a simple problem but I have been struggling with it for
some
> time. I am trying to determine if a user supplied variable is a number.
The
> user inputs a value (their age) in an input text box. This means the value
is
> of type 'String". Using various functions, such as typeof, parseInt and
the
> Number object I can get a return of NaN if the value is not a number.
However I
> simply cannot use the return in an if statement eg if (age == NaN) of
if(age ==
> 'NaN') just simply does not evaluate.
>
> Any suggestions?
>

> You can restrict the input to numbers only...
> Example: input text box named agebox:
> agebox.restrict = "0-9";
>
> Here is restriction for alpha letters only...
> agebox.restrict = "a-z A-Z";
>
> Here is restriction for letters and numbers only without punctuation etc..
> agebox.restrict = "a-z A-Z 0-9";
>
> If the number of chars input is 0, don't evaluate it.
> hth
> tralfaz

"mitsubishi" <webforumsuser@macromedia.com> wrote in message
news:c284tb$f3d$1@forums.macromedia.com...
> This probably is a simple problem but I have been struggling with it for
some
> time. I am trying to determine if a user supplied variable is a number.
The
> user inputs a value (their age) in an input text box. This means the value
is
> of type 'String". Using various functions, such as typeof, parseInt and
the
> Number object I can get a return of NaN if the value is not a number.
However I
> simply cannot use the return in an if statement eg if (age == NaN) of
if(age ==
> 'NaN') just simply does not evaluate.
>
> Any suggestions?
>