What are the hook functions provided by directives?
Interviewer Expectations for this Question
01
Core Competency
Assesses fundamental understanding of Vue.js conventions, runtime behavior, and memory/performance considerations.
02
Evaluation Criteria
Hiring managers look for precision, avoidance of ambiguous jargon, and ability to explain trade-offs under real production conditions.
Comprehensive Model Answer
Verified Solution
A directive object can provide several hook functions,
- bind: This occurs once the directive is attached to the element.
- inserted: This hook occurs once the element is inserted into the parent DOM.
- update: This hook is called when the element updates, but children haven't been updated yet.
- componentUpdated: This hook is called once the component and the children have been updated.
- unbind: This hook is called only once when the directive is removed.
Note: There are several arguments that can be passed to the above hooks.
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