Chapter 11. Number()

Conceptual Overview of Using the Number() Object

The Number() constructor function is used to create numeric objects and numeric primitive values.

In the code below, I detail the creation of numeric values in JavaScript.

Live Code

<!DOCTYPE html><html lang="en"><body><script>

// create number object using the new keyword and the Number() constructor
var numberObject = new Number(1);
console.log(numberObject); // logs 1
console.log(typeof numberObject) // logs 'object'

// create number literal/primitive using the number constructor without new
var numberObjectWithOutNew = Number(1); // without using new keyword
console.log(numberObjectWithOutNew); // logs 1
console.log(typeof numberObjectWithOutNew) // logs 'number'

// create number literal/primitive (constructor leveraged behind the scene)
var numberLiteral = 1;
console.log(numberLiteral); // logs 1
console.log(typeof numberLiteral); // logs 'number'


</script></body></html>

Integers and Floating-Point Numbers

Numbers in JavaScript are typically written as either integer values or floating point values. In the code below, I create a primitive integer number and a primitive floating point number. This is the most common usage of number values in JavaScript.

Live Code

<!DOCTYPE html><html lang="en"><body><script>

var integer = 1232134;
console.log(integer); // logs '1232134'

var floatingPoint = 2.132;
console.log(floatingPoint); // logs '2.132'

</script></body></html>

Note

In JavaScript, a numeric value can be a hexadecimal ...

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