How Can I Efficiently Determine Element Visibility in JavaScript?

Determining Element Visibility in the DOM with Pure JavaScript

Identifying whether an element is visible within the DOM is often essential for various web development tasks. While jQuery offers a simple solution, this article explores a pure JavaScript approach.

Checking Element Attributes

The question proposes checking attributes such as display and visibility to determine visibility. However, these attributes alone may not be sufficient.

Leveraging Element Offset

According to the MDN documentation, an element's offsetParent property returns null if the element or its ancestors are hidden by the display property. This approach is suitable if there are no elements with position: fixed.

function isHidden(el) {
    return (el.offsetParent === null);
}

Window Styling for Fixed Elements

If position-fixed elements are present, it is necessary to use window.getComputedStyle().

function isHidden(el) {
    var style = window.getComputedStyle(el);
    return (style.display === 'none');
}

Performance Considerations

Option 2 with window.getComputedStyle() is more comprehensive but potentially slower. If this operation is repeated frequently, consider using the offset approach for performance optimization.

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