JAVASCRIPT

JavaScript Number() Function

0hee 2007. 10. 10. 11:12

Definition and Usage

The Number() function converts the value of an object to a number.

Syntax

Number(object)

Parameter Description
object Required. A JavaScript object


Tips and Notes

Note: If the parameter is a Date object, the Number() function returns the number of milliseconds since midnight January 1, 1970 UTC.

Note: If the object's value cannot be converted to a number, the Number() function returns NaN.


Example

In this example we will try to convert different objects to numbers:

<script type="text/javascript">
var test1= new Boolean(true)
var test2= new Boolean(false)
var test3= new Date()
var test4= new String("999")
var test5= new String("999 888")
document.write(Number(test1)+ "<br />")
document.write(Number(test2)+ "<br />")
document.write(Number(test3)+ "<br />")
document.write(Number(test4)+ "<br />")
document.write(Number(test5)+ "<br />")
</script>

The output of the code above will be:

1
0
1191982263694
999
NaN


Try-It-Yourself Demos

Number()
How to use Number().