Number.prototype.toString()
The toString()
method returns a string representing the specified Number
object.
Syntax
<var>numObj</var>.toString([<var>radix</var>])
Parameters
radix
- Optional. An integer between 2 and 36 specifying the base to use for representing numeric values.
Return value
A string representing the specified Number
object.
Exceptions
RangeError
- If
toString()
is given a radix not between 2 and 36, aRangeError
is thrown.
Description
The Number
object overrides the toString()
method of the Object
object; it does not inherit Object.prototype.toString()
. For Number
objects, the toString()
method returns a string representation of the object in the specified radix.
The toString()
method parses its first argument, and attempts to return a string representation in the specified radix (base). For radixes above 10, the letters of the alphabet indicate numerals greater than 9. For example, for hexadecimal numbers (base 16), a
through f
are used.
If the radix
is not specified, the preferred radix is assumed to be 10.
If the numObj
is negative, the sign is preserved. This is the case even if the radix is 2; the string returned is the positive binary representation of the numObj
preceded by a -
sign, not the two's complement of the numObj
.
If the numObj
is not a whole number, the 'dot' sign is used to separate the decimal places.
Examples
Using toString
var count = 10; console.log(count.toString()); // displays '10' console.log((17).toString()); // displays '17' console.log((17.2).toString()); // displays '17.2' var x = 6; console.log(x.toString(2)); // displays '110' console.log((254).toString(16)); // displays 'fe' console.log((-10).toString(2)); // displays '-1010' console.log((-0xff).toString(2)); // displays '-11111111'
Specifications
Specification | Status | Comment |
---|---|---|
ECMAScript 1st Edition (ECMA-262) | Standard | Initial definition. Implemented in JavaScript 1.1. |
ECMAScript 5.1 (ECMA-262) The definition of 'Number.prototype.tostring' in that specification. |
Standard | |
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'Number.prototype.tostring' in that specification. |
Standard | |
ECMAScript 2017 Draft (ECMA-262) The definition of 'Number.prototype.tostring' in that specification. |
Draft |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |
Feature | Android | Chrome for Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |
See also
License
© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-us/docs/web/javascript/reference/global_objects/number/tostring