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Getting Object "type"

Hello All:
I would like to expand upon the typeof operator.
Using 'typeof' I can distinguish between string and
array for instance, because typeof returns "object" for
array.

How can I programmaticall y distinguish between an Array and an Option,
for instance?

Thanks
Tim
Jul 23 '05 #1
4 5020
Tim Johnson wrote:
Hello All:
I would like to expand upon the typeof operator.
Using 'typeof' I can distinguish between string and
array for instance, because typeof returns "object" for
array.

How can I programmaticall y distinguish between an Array and an Option,
for instance?


alert([1,2,3].constructor == Array)

Mick
Jul 23 '05 #2
Mick White wrote:
<...>
How can I programmaticall y distinguish between an Array and an Option,
for instance?


alert([1,2,3].constructor == Array)


Eureka!
thanks
tj
Jul 23 '05 #3

Well, there's a typeof OBJHERE:

typeof ARRHERE; will return 'array' of a function 'function' of a string
a 'string' and such.

Danny
On Mon, 27 Jun 2005 15:47:53 -0700, Tim Johnson <ti*@johnsons-web.com>
wrote:
Hello All:
I would like to expand upon the typeof operator.
Using 'typeof' I can distinguish between string and
array for instance, because typeof returns "object" for
array.

How can I programmaticall y distinguish between an Array and an Option,
for instance?

Thanks
Tim


--
Using Opera's revolutionary e-mail client: http://www.opera.com/mail/
Jul 23 '05 #4
On 26/06/2005 06:30, Danny wrote:

[snip]
typeof ARRHERE; will return 'array' [...]


No, it won't. There are a limited number of returned types, and they
correspond to the primitives (boolean, number, string, and undefined)
with the addition of object, which is a catch-all for all objects
(including arrays).

The null type, which is also a primitive, does not have its own value
and is classified as an object. Functions are also an exception but
unlike null, they /do/ have their own value.

[snipped top-post]

Stop top-posting. This group has posting rules - follow them.

Mike

--
Michael Winter
Replace ".invalid" with ".uk" to reply by e-mail.
Jul 23 '05 #5

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