Determining if a var is a number

[mitsubishi]

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?

[James Fee]

Look up how to use isNaN().

Jim
"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?
>

[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?
>

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

[tralfaz]

BTW.. If you prefer not to use actionscript, you can also restrict the input
text box to numerals only by selecting properties for the input text box:
Properties..
Character button...
Check mark ONLY..
Check mark Numerals (0-9)
tralfaz

> 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