JavaScript: The Definitive Guide, Fourth Edition

Name

Number — support for numbers

Availability

JavaScript 1.1; JScript 2.0; ECMAScript v1

Inherits from/Overrides

Inherits from Object

Constructor

new Number(value) Number(value)

Arguments

value: The numeric value of the Number object being created, or a value to be converted to a number.

Returns

When Number( ) is used with the new operator as a constructor, it returns a newly constructed Number object. When Number( ) is invoked as a function without the new operator, it converts its argument to a primitive numeric value and returns that value (or NaN if the conversion failed).

Constants

Number.MAX_VALUE: The largest representable number.
Number.MIN_VALUE: The smallest representable number.
Number.NaN: Not-a-number value.
Number.NEGATIVE_INFINITY: Negative infinite value; returned on overflow.
Number.POSITIVE_INFINITY: Infinite value; returned on overflow.

Methods

toString( ): Converts a number to a string, using a specified radix (base).
toLocaleString( ): Converts a number to a string, using local number formatting conventions.
toFixed( ): Converts a number to a string that contains a specified number of digits after the decimal place.
toExponential( ): Converts a number to a string using exponential notation with the specified number of digits after the decimal place.
toPrecision( ): Converts a number to a string using the specified number of significant digits. Uses exponential or fixed-point notation depending on the size of the number and the number of significant digits specified.