在此页

• 句法
• 范例
• 规范
• 浏览器兼容性
• 相关话题

upgrade() 方法在 CustomElementRegistry interface upgrades all shadow-containing custom elements in a 节点 subtree, even before they are connected to the main document.

句法

customElements.upgrade(root);
					

参数

root

节点 instance with shadow-containing descendant elements that are to be upgraded. If there are no descendant elements that can be upgraded, no error is thrown.

返回值

Void.

范例

Taken from the HTML spec :

const el = document.createElement("spider-man");
class SpiderMan extends HTMLElement {}
customElements.define("spider-man", SpiderMan);
console.assert(!(el instanceof SpiderMan)); // not yet upgraded
customElements.upgrade(el);
console.assert(el instanceof SpiderMan);    // upgraded!
					

规范

规范	状态	注释
HTML 实时标准 The definition of 'customElements.upgrade()' 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
upgrade	Chrome 68	Edge 79	Firefox 63	IE 不支持 No	Opera 55	Safari ?	WebView Android 68	Chrome Android 68	Firefox Android 63	Opera Android 48	Safari iOS ?	Samsung Internet Android 10.0

图例

完整支持

完整支持

不支持

不支持

兼容性未知 ?

兼容性未知

实验。期望将来行为有所改变。

实验。期望将来行为有所改变。

元数据

• 最后修改： Mar 18, 2019

相关话题

1. CustomElementRegistry
2. 方法

   1. define()
   2. get()
   3. upgrade()
   4. whenDefined()