Deepen your understanding of Vue lifecycle hooks with this targeted quiz designed to assess and reinforce your grasp of key hook behaviors, phases, and practical scenarios in modern Vue development.
Which Vue lifecycle hook is called immediately after a component instance has been created but before it is mounted to the DOM, allowing access to reactive data for initial setup?
Explanation: The 'created' hook is triggered after the component instance is created and reactive data are initialized, but before the DOM is mounted. This makes it ideal for setting up data or fetching remote resources. 'mounted' occurs after the DOM mounting, 'beforeMount' is just before mounting, and 'beforeCreate' runs before data observation and event configuration, so you cannot access reactive properties in 'beforeCreate'.
If you need to directly manipulate the DOM element rendered by a Vue component, which lifecycle hook should you use to ensure the DOM is available?
Explanation: The 'mounted' hook is called after the component has been mounted to the DOM, making it safe to access and manipulate rendered elements. In contrast, 'created' happens before the DOM exists, 'updated' is called after every reactive update, and 'beforeDestroy' is used for cleanup before a component is removed, not for initial DOM access.
Which lifecycle hook is ideal for performing actions each time a reactive property in a component changes and the DOM has just been updated?
Explanation: 'updated' runs after data changes are reflected in the DOM, which is useful for responding to completed updates or triggering animations. 'beforeUpdate' fires before the DOM re-renders and should not be used for post-render actions. 'mounted' is only called once after mounting, and 'destroyed' occurs after the component has been removed.
Which Vue lifecycle hook is most appropriate for clearing intervals, detaching event listeners, or performing cleanup just before a component instance is destroyed?
Explanation: 'beforeDestroy' is the correct hook for cleanup since it is called right before the instance is destroyed, allowing you to safely terminate background tasks. 'destroyed' occurs after destruction, which may be too late for cleanup. 'beforeMount' and 'beforeUpdate' are related to rendering phases and not to the removal of the component.
Given a newly created Vue component, which sequence correctly reflects the order in which the following lifecycle hooks are called: beforeCreate, created, beforeMount, mounted?
Explanation: The lifecycle hooks are called in this specific order: 'beforeCreate,' then 'created,' followed by 'beforeMount,' and finally 'mounted.' This reflects initialization, data readiness, preparation to mount, and completion of mounting. Options mixing up this sequence are incorrect and would not reflect the way Vue manages component initialization.