How to Trigger Events When DOM Attributes Change?

Attribute Change Event Handling

Is it possible to activate an event when a DOM attribute changes? For instance, when the source of an image or the inner HTML of a division is modified?

Mutation Events provide a solution to this issue. While browser support for these events is limited, they offer a way to monitor attribute changes.

Specifically, you can utilize the MutationObserver interface as a replacement for Mutation Events. MutationObserver provides a more standardized and reliable method for observing DOM changes, including attribute modifications.

Here's how you can use MutationObserver to trigger a custom event when an attribute changes:

const observer = new MutationObserver((mutations) => {
  mutations.forEach((mutation) => {
    if (mutation.type === 'attributes') {
      const element = mutation.target;
      const attributeName = mutation.attributeName;
      const oldValue = mutation.oldValue;
      const newValue = mutation.newValue;

      // Trigger custom event with relevant information
      element.dispatchEvent(new CustomEvent('attributeChanged', {
        detail: {
          attributeName,
          oldValue,
          newValue
        }
      }));
    }
  });
});

// Observe the DOM element for attribute changes
observer.observe(document.querySelector('#myElement'), { attributes: true });

By using MutationObserver, you can effectively track attribute changes and initiate custom events accordingly, allowing you to respond to dynamic DOM modifications.

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