Vue – When and Why Using $el

In Vue.js, $el is a property available on Vue instances that refers to the root DOM element associated with the Vue instance. It provides direct access to the underlying native DOM element, allowing you to perform DOM manipulation or access properties and methods that are not directly exposed by Vue.js.
Here’s when and why you might use $el:

1. Direct DOM Manipulation:

You can use $el to directly manipulate the DOM element associated with a Vue instance. This can be useful when you need to perform low-level DOM operations that are not covered by Vue’s reactivity system, such as setting focus, adding event listeners, or accessing native properties and methods of DOM elements.

mounted() {
 // Set focus to the input element associated with this Vue instance
 this.$el.querySelector('input').focus();
}

2. Integrating with Third-party Libraries:

If you’re using third-party libraries that expect a native DOM element as input, you can use $el to provide the root element of the Vue instance.

mounted() {
 // Initialize a third-party library with the root element of the Vue instance
 ThirdPartyLibrary.initialize(this.$el);
}

3. Debugging:

During development or debugging, you might use $el to inspect the underlying DOM structure of a Vue component directly from the browser’s developer tools.

mounted() {
 console.log(this.$el); // Output the root DOM element to the console
}

4. Performance Optimization:

In some cases, accessing $el directly can be more efficient than relying on Vue’s virtual DOM, especially for operations that don’t require reactivity or component updates.

const inputElement = this.$el.querySelector('input');
// Perform some operations on the input element without triggering Vue's reactivity

However, it’s important to use $el judiciously and consider whether there’s a better, more idiomatic way to achieve your goals within the Vue.js framework. Direct DOM manipulation using $el bypasses Vue’s reactivity system, which can lead to unexpected behavior if not used carefully. Whenever possible, prefer Vue’s declarative approach to managing the DOM through templates and data bindings.