When Style.display Doesn\'t Work: How to Retrieve True Display Property of DOM Elements?

Retriving Display Property of DOM Elements: Unraveling the Style Anomaly

In web development, accessing the display property of DOM elements is crucial. However, a common misconception arises when using the ".style.display" property, as exemplified by the HTML snippet provided.

The initial confusion stems from the discrepancy in the results obtained. While one would expect to retrieve "none" and "block" for the anchor and paragraph elements, respectively, the alerts display empty strings instead. This seemingly anomalous behavior has led developers to question the effectiveness of ".style.display" for retrieval purposes.

Understanding the Discrepancy

The key to understanding this discrepancy lies in the nature of ".style.display". It operates directly on the "style" attribute, which represents the explicit style specified in the HTML document. However, the display property we observe is not always derived solely from the style attribute. Commonly, it is the result of various factors, including CSS rules, browser defaults, and external stylesheets.

The Solution: getComputedStyle

To accurately retrieve the applied style, the solution is to leverage the "getComputedStyle" method. This method returns a CSSStyleDeclaration object that represents the computed style of the element, considering all relevant factors.

Example with getComputedStyle

The following code snippet demonstrates how to correctly retrieve the display property using "getComputedStyle":

<code class="javascript">var p = document.getElementById('p');
var display = window.getComputedStyle(p, null).getPropertyValue('display');
alert(display); // Output: block</code>

In this example, the "display" property is successfully retrieved and displayed, revealing the correct value of "block."

Conclusion

While ".style.display" provides a way to modify the style attribute, it is not the ideal choice for retrieving the computed display property. For accurate retrieval, "getComputedStyle" should be employed, ensuring that the resulting display value reflects the actual state of the element.

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