Course Content
VUE Tutorial
About Lesson

beforeDestroy, destroyed

In the world of Vue.js, lifecycle hooks play a crucial role in managing the various stages a component goes through. In this post, we will delve into two significant hooks – beforeDestroy and destroyed – exploring their functionalities and how they impact Vue.js applications.

The Lifecycle of a Vue Component

Before diving into the specifics of beforeDestroy and destroyed, let’s briefly revisit the Vue component lifecycle. Vue instances go through a series of initialization steps, updates, and destruction. Understanding these phases is vital for effective Vue.js development.

The beforeDestroy Hook


The beforeDestroy hook is invoked just before a Vue instance is destroyed. This is the ideal place to perform cleanup tasks, unbind event listeners, or clear up resources associated with the component.

Use Cases

  • Cleaning Up Timers: If your component involves timers or intervals, beforeDestroy is the perfect spot to clear them, preventing memory leaks.
  • Event Listener Removal: Unregistering global or external event listeners ensures your application doesn’t hold onto unnecessary references after the component is no longer needed.
  • Custom Cleanup Logic: Execute any custom cleanup logic specific to your component.

The destroyed Hook


Following the destruction of a Vue instance, the destroyed hook is triggered. This stage indicates that the component has been fully torn down, and its resources have been released.

Use Cases

  • Final Cleanup: Perform any last-minute cleanup or operations that are dependent on the component’s complete destruction.
  • Post-Destruction Logging: If you need to log information or trigger actions after the component is destroyed, the destroyed hook is the place to do it.

Best Practices and Tips

  • Avoid Async Operations: While you can perform asynchronous operations in these hooks, it’s generally safer to keep them synchronous to prevent unexpected behaviors.
  • Utilize vm.$destroyed: Vue provides the $destroyed property, a boolean that indicates whether a component has been destroyed. It can be useful for conditional logic within your component.