Why Avoid Accessing Elements Directly by Their ID in JavaScript?

Why Don't We Just Use Element IDs as Identifiers in JavaScript?

Many browsers allow accessing an element with id="myDiv" by simply writing myDiv, as demonstrated in the provided code sample. However, documentation for this method is surprisingly scarce, with sources recommending the use of document.getElementById("myDiv") or document.querySelector("#myDiv") instead.

Concerns with Using Element IDs as Identifiers:

Apart from code design aesthetics, using the short form has some potential issues:

• Unintentional Global Variable Creation: Using element IDs directly creates implicitly-declared global variables, which can lead to potential conflicts with other code or libraries.
• Lack of Standards Compliance: The promotion of id values into global variables is not explicitly mentioned in the HTML5 spec for the id attribute. While some browsers may support it, it is not guaranteed for all future browsers.
• Discouraged by the HTML5 Spec: Although standards compliant, the HTML5 spec advises against using this pattern, stating that it can lead to brittle code and recommends using document.getElementById() or document.querySelector() instead.

Conclusion:

While using element IDs as identifiers in JavaScript may provide a short-cut, it is not recommended due to its lack of documentation, potential for unintended global variable creation, and discouragement by the HTML5 spec. It is more reliable and maintainable to use the recommended methods of document.getElementById() or document.querySelector().

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