Use typeof("variable")
eg. if (typeof(top.frames) = "undefined") return;
----- Original Message -----
From: "Craig Michael Nathan" <cnathan at MEconomy.com>
To: <javascript at LaTech.edu>
Sent: Thursday, June 07, 2001 2:01 PM
Subject: [Javascript] Testing for "undefined" (undefined vs. null)
> I have a wacky problem in that using
> top.frames
> sometimes returns "undefined".
>
> I'm curious how I can test for "undefined".
>
> I tried:
> if (top.frames == null) return;
>
> But have since learned that null != undefined
>
> Any ideas?
>
> Much appreciated,
>
> -Craig
>
>
> *****************************
> Craig Michael Nathan
> Chief Technology Officer
> MEconomy, Inc.
> cnathan at MEconomy.com
>
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