How to check undefined javascript value in facebook?

Posted by Murvinlai on Stack Overflow See other posts from Stack Overflow or by Murvinlai
Published on 2010-03-25T04:17:06Z Indexed on 2010/03/25 4:23 UTC
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Filed under:

facebook

|

undefined

|

JavaScript

In normal javascript, I can check either

if (i == undefined) or if (i === undefined)

or the "typeof"

however, within facebook, it will have the api_key append as the prefix in undefined.

i.e. it will become

if (a12345_i == a12345_undefined)

which is NOT undefined

so, what can I do to find out the variable is undefined or not?

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