Create undefined value by defining a variable without assigning value in JavaScript
Description
The following code shows how to create undefined value by defining a variable without assigning value.
Example
<!-- w ww . ja v a2 s. c o m-->
<!DOCTYPE html>
<html>
<head>
<script type="text/javascript">
var aString;
document.writeln(aString);
</script>
</head>
<body>
</body>
</html>
The code above generates the following result.
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