documentgetElementByIdcontent

documentgetElementByIdcontent is not a standard API in web development; the common and correct API is document.getElementById, which retrieves a DOM element by its unique id so its content can be accessed or modified.

document.getElementById is a method of the Document interface in the Web APIs. It returns the element whose id attribute matches the provided string, or null if no such element exists. The method is widely used to access a specific element in the DOM for reading or updating its content, attributes, or styles.

Syntax: document.getElementById(id) where id is a string representing the element’s id. If an element with that id exists, the method returns that element; otherwise, it returns null.

Using the retrieved element, you can obtain or change its content via properties such as textContent, innerText, or innerHTML, and you can also adjust attributes, styles, or event listeners. For example, if there is an element <div id="content">Hello</div>, calling document.getElementById("content") yields that element, from which you can read its text or replace it with new content.

Notes: IDs must be unique within a document. getElementById is optimized for direct ID-based access and is typically faster for this purpose than broader selector methods like querySelector. For more complex selection criteria, querySelector or querySelectorAll can be used.

See also: DOM, querySelector, innerHTML, textContent, element, Node.