Determining variable type

[mouseit]

If I have a variable of some sort, say x, how can I find out what
variable type javascript thinks it is? For example, if I've declared x
as 5 earlier, how do I know now whether it's a string or a number,
isNaN returns false, regardless of whether I declared it as "5" or 5.

[Lee]

mouseit said:

>
If I have a variable of some sort, say x, how can I find out what
variable type javascript thinks it is? For example, if I've declared x
as 5 earlier, how do I know now whether it's a string or a number,
isNaN returns false, regardless of whether I declared it as "5" or 5.

Javascript doesn't think it needs to know.
Why do you think you do?
--

[-Lost]

mouseit wrote:

If I have a variable of some sort, say x, how can I find out what
variable type javascript thinks it is? For example, if I've declared x
as 5 earlier, how do I know now whether it's a string or a number,
isNaN returns false, regardless of whether I declared it as "5" or 5.

typeof or instanceof.

typeof will give the generic object type.
instanceof will only return true if it is an object of type [Object].
([Object] being any valid JavaScript Object; String, Function, Array,
Object, whatever.)

--
-Lost
Remove the extra words to reply by e-mail. Don't e-mail me. I am
kidding. No I am not.

[Douglas Crockford]

mouseit wrote:

If I have a variable of some sort, say x, how can I find out what
variable type javascript thinks it is? For example, if I've declared x
as 5 earlier, how do I know now whether it's a string or a number,
isNaN returns false, regardless of whether I declared it as "5" or 5.

typeof 5 === 'number'
typeof '5' === 'string'

http://javascript.crockford.com/survey.html

[mouseit]

On May 26, 8:58 pm, Douglas Crockford <[e-mail]:

mouseit wrote:

If I have a variable of some sort, say x, how can I find out what
variable type javascript thinks it is? For example, if I've declared x
as 5 earlier, how do I know now whether it's a string or a number,
isNaN returns false, regardless of whether I declared it as "5" or 5.

typeof 5 === 'number'
typeof '5' === 'string'

http://javascript.crockford.com/survey.html

Thank you all!