Detecting an undefined object property in JavaScript

Posted by Matt Sheppard on Stack Overflow See other posts from Stack Overflow or by Matt Sheppard
Published on 2008-08-26T07:25:08Z Indexed on 2010/04/01 12:43 UTC
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JavaScript

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beginner

What's the best way of checking if an object property in JavaScript is undefined?

Sorry, I initially said variable rather than object property. I believe the same == undefined approach doesn't work there.

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