How Can I Accurately Determine Element Visibility in the DOM Using Pure JavaScript?

Visibility Detection in the DOM

When working with elements in the Document Object Model (DOM), it's often necessary to determine whether an element is visible. In pure JavaScript, without the use of libraries like jQuery, checking for visibility requires a closer examination of specific HTML attributes.

To determine the visibility of an element, consider the following attributes:

• display: This attribute specifies the display behavior of an element. If set to "none," the element is hidden.
• visibility: This attribute controls the visibility of an element, allowing it to be hidden or visible.

In the issue raised, the user attempted to use window.getComputedStyle(my_element)['display']) to check for visibility, but it was not accurate.

However, an alternative approach is available to check for element visibility using its offsetParent property. If an element or any of its parents has the display property set to "none," its offsetParent will be null. This can be used to determine whether an element is visible or not.

For elements without fixed positioning, the following function can be used:

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

For elements with fixed positioning, a more precise approach is to use window.getComputedStyle(), which accounts for more edge cases.

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

This method is more comprehensive but slower than the previous one. If speed is a concern, it's best to use the offsetParent property when possible.

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