JavaScript NaN Property: Number Object
Description
The NaN property of number object represents a value that is not a number. JavaScript prints the value as NaN.
Version
Implemented in JavaScript 1.1
Syntax
Number.NAN
Example:
The following web document demonstrates how the NaN() property can be used.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="content-type" content="text/html; charset=iso-8859-1" />
<title>JavaScript Number object - NAN property example</title>
</head>
<body>
<h1 style="color: red">JavaScript Number object : NAN property</h1>
<hr />
<script type="text/javascript">
//This is done to make the following JavaScript code compatible to XHTML. <![CDATA[
if(123 == Number.NaN)
{
document.write("This is not a number.... " + "<br>");
}
else
{
document.write("It is a number...." + "<br>");
}
var week = 17;
if ( week < 1 || week > 7)
{
week = Number.NaN;
document.write(week);
}
//]]>
</script>
</body>
</html>
View the example in the browser
Supported Browser
| Internet Explorer 7 | Firefox 3.6 | Google Chrome 7 | Safari 5.0.1 | Opera 10 |
| Yes | Yes | Yes | Yes | Yes |
See also:
New Content: Composer: Dependency manager for PHP, R Programming