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

Distinguishing Between currentTarget and target Properties in JavaScript Events

When handling events in JavaScript, it's essential to understand the distinction between the currentTarget and target properties. These properties provide valuable insights into the event propagation mechanism and play crucial roles in various scenarios.

Event Propagation and Property Differences

By default, events in JavaScript follow a bubbling propagation model. This means that an event originates from a specific element and propagates upward through its parent elements until it reaches the document object. During this propagation, the target property refers to the element that initially triggered the event, while the currentTarget property identifies the element that the event listener is attached to.

Example

Consider an HTML document containing two nested divs:

<div>

Now, we attach an event listener to the outer div:

document.getElementById("div-container").addEventListener("click", function(event) {
  console.log(`Target: ${event.target.id}, CurrentTarget: ${event.currentTarget.id}`);
});

If we click on the inner div, both the target and currentTarget properties will output "div-inner," indicating that the event originated from the inner div. However, if we click on the outer div, the currentTarget property will still output "div-container" since the event listener is attached to the outer div, while the target property will be null because the click event was not directly triggered on the outer div.

Use Cases

Uses of target:

• Identifying the specific element that caused the event
• Limiting event handling to a particular element in nested structures
• Determining the element's precise location on the page

Uses of currentTarget:

• Determining the element that the event listener is attached to
• Controlling event propagation by stopping further bubbling or capturing additional events
• Implementing event delegation for handling events on multiple elements with a single event listener

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