What is undefined value means in JavaScript?

 Posted by Virendradugar on 12/16/2009 | Category: JavaScript Interview questions | Views: 4559

There can be multiple reasons of having undefined values
1. Object does not exist. Like you create an object of a control which does not exists in your page and when you access it, it is undefined.
2. No value is assigned to the object.
3. If you are trying to access a property which does not exists for the object.

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