W3cubDocs

Node: isConnected property

The read-only isConnected property of the Node interface returns a boolean indicating whether the node is connected (directly or indirectly) to a Document object.

Value

A boolean value that is true if the node is connected to its relevant context object, and false if not.

Examples

Standard DOM

A standard DOM example:

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

Shadow DOM

A shadow DOM example:

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

// Create some CSS to apply to the shadow DOM
const 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;
  positions: 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

Specifications

Specification
DOM Standard # ref-for-dom-node-isconnected①

Browser compatibility