DOMTokenList.keys()

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句法
范例
规范
浏览器兼容性
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keys() 方法在 DOMTokenList interface returns an iterator allowing to go through all keys contained in this object. The keys are of type unsigned integer .

句法

tokenList.keys();

参数

None.

返回值

返回 iterator .

范例

In the following example we retrieve the list of classes set on a <span> element as a DOMTokenList 使用 Element.classList . We when retrieve an iterator containing the keys using values() , then iterate through those keys using a for ... of loop, writing each one to the <span> 's Node.textContent .

First, the HTML:

<span class="a b c"></span>

Now the JavaScript:

var span = document.querySelector("span");
var classes = span.classList;
var iterator = classes.keys();
for(var value of iterator) {
  span.textContent += value + ' ++ ';
}

输出看起来像这样：

规范

规范	状态	注释
DOM The definition of 'keys() (as iterable<Node>)' in that specification.	实时标准	初始定义

浏览器兼容性

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request. 更新 GitHub 上的兼容性数据

	桌面						移动
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`keys`	Chrome 45	Edge ≤79	Firefox 50	IE 不支持 No	Opera 32	Safari 10	WebView Android 45	Chrome Android 45	Firefox Android 50	Opera Android 32	Safari iOS 10	Samsung Internet Android 5.0

图例

完整支持
不支持

元数据

最后修改： Jun 22, 2020

DOM (文档对象模型)
DOMTokenList
特性
1. length
方法
1. add()
2. contains()
3. entries()
4. forEach()
5. item()
6. keys()
7. remove()
8. replace()
9. supports()
10. toggle()
11. value
12. values()
DOM 相关页面

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句法

参数

返回值

范例

规范

浏览器兼容性

图例

相关话题