How can I determine if a variable is undefined or null

0 votes

How do I determine if variable is undefined or null?

My code is as follows:

var EmpName = $("div#esd-names div#name").attr('class');
if(EmpName == 'undefined'){
  // DO SOMETHING
};
<div id="esd-names">
  <div id="name"></div>
</div>

But if I do this, the JavaScript interpreter halts execution.

Aug 28, 2020 in Java-Script by kartik
• 37,490 points
71 views

1 answer to this question.

0 votes

Hello @kartik,

You can use the qualities of the abstract equality operator to do this:

if (variable == null){
    // your code here.
}

Because null == undefined is true, the above code will catch both null and undefined.

Hope it helps!!

Thank You!!

answered Aug 28, 2020 by Niroj
• 82,580 points

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