Node.isConnected

isConnected 是 Node 的一个只读属性接口。无论节点是否与 DOM 树连接,该属性都会返回一个布尔值。例如: Document 对象与一般 DOM 树连接,ShadowRoot 与 shadow DOM 连接。

语法

var isItConnected = nodeObjectInstance.isConnected

返回值

返回 布尔值 — 如果该节点与 DOM 树连接则返回 true, 否则返回 false

样例

标准 DOM 树

let test = document.createElement('p');
console.log(test.isConnected); // Returns false
document.body.appendChild(test);
console.log(test.isConnected); // Returns true

Shadow DOM 树

// Create a shadow root
var shadow = this.attachShadow({mode: 'open'});

// Create some CSS to apply to the shadow dom
var style = document.createElement('style');
console.log(style.isConnected); // returns false

style.textContent = '.wrapper {' +
                       'position: relative;' +
                    '}' +

                     '.info {' +
                        'font-size: 0.8rem;' +
                        'width: 200px;' +
                        'display: inline-block;' +
                        'border: 1px solid black;' +
                        'padding: 10px;' +
                        'background: white;' +
                        'border-radius: 10px;' +
                        'opacity: 0;' +
                        'transition: 0.6s all;' +
                        'position: absolute;' +
                        'bottom: 20px;' +
                        'left: 10px;' +
                        'z-index: 3;' +
                      '}' +

// Attach the created style element to the shadow dom

shadow.appendChild(style);
console.log(style.isConnected); // Returns true

规范

规范 状态 备注
DOM
isConnected
Living Standard Initial definition.

浏览器兼容性

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!
Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
isConnectedChrome Full support 51Edge No support NoFirefox Full support 53IE No support NoOpera Full support 38Safari Full support 10.1WebView Android Full support 51Chrome Android Full support 51Firefox Android Full support 45Opera Android Full support 41Safari iOS Full support 10.1Samsung Internet Android Full support 6.0

Legend

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