JavaScript Event Handling: What's the Difference Between `currentTarget` and `target`?

JavaScript: Unveiling the Distinction Between CurrentTarget and Target Properties in Event Handling

In the realm of JavaScript event handling, the currentTarget and target properties hold distinct roles in understanding the event propagation mechanism.

Definition:

• target: Represents the immediate element that initiated the event. This is typically the element where the triggering action originated, such as a click or hover.
• currentTarget: Refers to the element where the event listener is attached. It indicates the current element in the event bubble path.

Event Bubbling and Capturing:
Events follow a default bubbling behavior in JavaScript. This means that an event triggered on an inner element will propagate (bubble) up the DOM tree to its ancestors.

Role of Properties:
During event propagation, both currentTarget and target provide valuable information:

• target: Identifies the element that originally caused the event, regardless of the propagation phase.
• currentTarget: Dynamically updates as the event bubbles up the DOM hierarchy. It points to the element where the event listener is currently being handled.

Scenarios and Use Cases:

• Event Propagation Control:

  • By capturing the event in the parent element (event capturing), the currentTarget will always refer to the parent, while the target will indicate the child element that triggered the event.
  • By bubbling the event to the document object (event bubbling), both currentTarget and target will align with the same element throughout the propagation.

• Element Isolation:

  • Using currentTarget, event handling can be isolated to specific elements by attaching listeners to their parent elements. The element that initiated the event can still be identified through the target property.

Example:

const parent = document.querySelector(".parent");
parent.addEventListener("click", (event) => {
  console.log("currentTarget:", event.currentTarget); // Parent element
  console.log("target:", event.target); // Clicked child element
});

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