What is js bubbling event

js bubbling event is an event model used to describe how events propagate in the DOM structure. This model is based on the concepts of event bubbling and event capture. Event bubbling is part of the event model, which describes how when a specific event occurs on an element, the event propagates to the upper layers of the DOM structure. If an event occurs on an element, the event will not only be triggered on the element, but also on its parent element, the parent element's parent element, and so on, until it reaches the outermost element, usually the document object. This process is called event bubbling.

The operating system for this tutorial: Windows 10 system, DELL G3 computer.

In JavaScript, bubbling events are an event model that describes how events propagate in the DOM (Document Object Model) structure. This model is based on the concepts of event bubbling and event capturing.

Event bubbling is part of the event model. It describes how when a specific event (such as click, mouse movement, etc.) occurs on an element (such as a button, link, etc.), this event is propagated to the upper layer of the DOM structure. . Specifically, if an event occurs on an element, the event will not only be triggered on that element, but also on its parent element, the parent element's parent element, and so on, until it reaches the outermost element, usually Is the document object. This process is called event bubbling.

The following is a simple example of how event bubbling works:

document.getElementById("myButton").addEventListener("click", function() {  
  alert("Button was clicked!");  
});  
  
document.body.addEventListener("click", function() {  
  alert("Body was clicked!");  
});

In this example, when the user clicks the button with the ID "myButton", it will be triggered first The click event of the button, and then due to the event bubbling, the click event will propagate to the upper level, triggering the click event of the body element. So if the user clicks the button, they will see two alert boxes: first "Button was clicked!" and then "Body was clicked!".

This feature allows us to handle events more flexibly in code. For example, we can choose to handle the event on a specific element, or handle the event when it bubbles to outer elements.

The opposite of event bubbling is event capture. Event capture means that when a specific event occurs on an element, the event is first triggered on the outermost element and then propagates to the inner layer until it reaches the element where the event occurred. However, in the default behavior of JavaScript, event handlers are usually called during the bubbling phase of the event.

In general, event bubbling is a model that describes how events propagate in the DOM structure. It allows us to handle various user interface events in a more appropriate place.

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