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In JavaScript how to check if a variable is null/undefined?

+1 vote
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In JavaScript how to check if a variable is null/undefined?
posted Aug 4, 2014 by anonymous

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1 Answer

0 votes

In Javascript you can check by using typeof for undefined variables

Example:

if(typeof(variable) == 'undefined')
    {
        alert("Variable is undefined");
    }
if(variable == null) 
   {
       alert("Variable is null");
   }
answer Aug 8, 2014 by Manish Tiwari
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