isElement#

Checks whether the given value is a DOM Element.

Usage Scenarios#

• DOM Manipulation: When working with the Document Object Model, you need to ensure that a certain value is a DOM Element before performing operations like adding classes, modifying attributes, or appending child nodes.
• Function Parameter Validation: In a function where a DOM Element is expected as a parameter, you can use the isElement method to verify the parameter type, avoiding errors caused by passing non - Element values.
• Conditional Judgment: Execute different logic based on whether a value is a DOM Element.

Examples#

import { isElement } from 'funtool';

const el = document.createElement('div');
if (isElement(el)) {
  el.classList.add('active');
}

const notEl = {};
if (!isElement(notEl)) {
  console.log('Not a DOM element');
}

Signature#

function isElement<T = unknown>(value: T): value is T & Element

Parameters#

• value (T): The value to check.

Returns#

• (value is T & Element): Returns true if the value is a DOM Element, and narrows the type to T & Element.