Number.isFinite()

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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.isFinite() method determines whether the passed value is finite.

In comparison to the global isFinite function, this method doesn't forcibly convert the parameter to a number. This means only values of the type number, that are also finite, return true.

Syntax

Number.isFinite(testValue);

Parameters

testValue
The value to be tested for finiteness.

Examples

Number.isFinite(Infinity);  // false
Number.isFinite(NaN);       // false
Number.isFinite(-Infinity); // false

Number.isFinite(0);         // true
Number.isFinite(2e64);      // true


Number.isFinite("0");       // false, would've been true with global isFinite("0")

Specifications

Specification Status Comment

ECMAScript Language Specification 6th Edition (ECMA-262)

 Draft Initial definition.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support 19.0 16.0 (16) Not supported 15.0 Not supported
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support ? ? 16.0 (16) ? ? ?

See also

  • The Number object it belongs to.

Document Tags and Contributors

タグ:
Contributors to this page: nikhilm, ethertank, fscholz, Waldo, Sheppy
最終更新者: fscholz,