新学一招, 判断一个js对象是不是数组

最新推荐文章于 2022-09-06 15:05:40 发布

原创最新推荐文章于 2022-09-06 15:05:40 发布 · 124 阅读

0 ·

CC 4.0 BY-SA版权

文章标签：

#prototype #360 #JavaScript #Google #Blog #ViewUI

web前端专栏收录该内容

85 篇文章

订阅专栏

本文介绍了一种简单可靠的JavaScript方法来判断一个对象是否为数组。该方法利用了Object.prototype.toString.call()函数，避免了因不同环境下构造函数不同导致的误判。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

从
[url]http://blog.360.yahoo.com/blog-TBPekxc1dLNy5DOloPfzVvFIVOWMB0li?p=916[/url]
学来一招, 判断一个js对象是不是数组


function isArray(o) {
  return Object.prototype.toString.call(o) === '[object Array]'; 
}

原文如下 :

[quote]
The Miller Device

The JavaScript language currently does not provide a good way to distinguish between objects and arrays. The typeof operator is broken: It identifies arrays as objects. Comparing a value's constructor property doesn't work because arrays created in a different frame will have a different constructor. There are do-it-yourself tests for arrayness, but they are complicated and unreliable.

Mark Miller of The Google, by closely reading the ECMAScript standard, has discovered a simpler, more reliable test.

Object.prototype.toString.apply(value) === '[object Array]'

[/quote]