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JavaScript: Check if sub variable defined

Posted on 2013-06-11
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Last Modified: 2013-06-11
How can I do this without errors?

 if (typeof (x) !== undefined && typeof (x.y) !== undefined) {
  alert('x.y not defined');
 }
 else {
  alert('x.y is defined');
 }

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Question by:hankknight
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leakim971 earned 2000 total points
ID: 39237807
"undefined" not undefined
test page : http://jsfiddle.net/awgLW/
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