This is an experimental technology, part of the Harmony (ECMAScript 6) proposal.
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future version of browsers as the spec changes.
Summary
The Number.isInteger() method determines whether the passed value is an integer.
If the target value is an integer, return true, otherwise return false.
If the value is NaN or infinite, return false.
Syntax
Number.isInteger(testValue)Parameters
-
testValue - The value to be tested for being an integer.
Example
Alert of some test values:
alert([ Number.isInteger(0.1), Number.isInteger(1), Number.isInteger(Math.PI) ]);
Polyfill
The following algorithm matches the one specified in ECMA harmony:
/*\
|*|
|*| :: Number.isInteger() polyfill ::
|*|
|*| https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/isInteger
|*|
\*/
if (!Number.isInteger) {
Number.isInteger = function isInteger (nVal) {
return typeof nVal === "number" && isFinite(nVal) && nVal > -9007199254740992 && nVal < 9007199254740992 && Math.floor(nVal) === nVal;
};
}
Specifications
| Specification | Status | Comment |
|---|---|---|
| Draft | Initial definition. |
Browser compatibility
| Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
|---|---|---|---|---|---|
| Basic support | 34 [1] | 16 (16) | Not supported | Not supported | Not supported |
| Feature | Android | Chrome for Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|---|
| Basic support | Not supported | Not supported | 16.0 (16) | Not supported | Not supported | Not supported |
[1] The feature is available behind a preference. In chrome://flags, activate the entry "Enable Experimental JavaScript".
See also
- The
Numberobject it belongs to.