


How to Correctly Modify HTML Element Styles Defined in External CSS Using JavaScript?
Modifying HTML Element Styles Defined in External CSS Using JavaScript
The task at hand involves altering the style of a
element, specifically changing its background color to green, when the associated "home" class is clicked. However, the implemented code appears to be faltering.
The Flaw in the Code:
The primary issue lies in the following line:
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This code employs the getElementsByClassName() method to obtain a node list of elements with the "home" class. However, the result is a node list, not a single element. Consequently, the subsequent .style = operation fails to modify the desired element's style.
The Correct Approach:
To successfully apply the color change, one must first obtain a reference to the specific element whose style needs to be altered. This can be achieved using the more precise method, querySelector():
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With this reference in hand, the style modification can be performed effectively:
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Additional Considerations:
It's worth noting that accessing elements directly via the DOM, as seen above, can be less efficient than utilizing event delegation. Furthermore, modern best practices encourage avoiding direct manipulation of the DOM altogether. Consider using CSS frameworks or libraries for styling purposes, thereby separating style and logic for enhanced code readability and maintainability.
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