Practice React Coding Challenges to Pass Your Interview
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Overview
Learn the difference between useState and useRef by creating two counters and observing how state and refs affect component rendering.
Requirements
- Create two counters: counter state and counter ref, each with increment and decrement buttons.
- The counter state should update and reflect its value in the UI when incremented or decremented.
- The counter ref should update its value when incremented or decremented without triggering a UI update.
- After triggering a rerender with the counter state, the counter ref should show its updated value.
Notes
- Understand the difference between
useStateanduseRefin React. - Learn how
useRefcan store mutable values without causing rerenders. - Practice triggering and observing rerenders with
useState. - Gain clarity on when to use
useStatevsuseRefdepending on UI updates.
Tests
- increment state value on plus button click
- decrement state value on minus button click
- does not update ref value in DOM without re-render
- displays updated ref value after state re-render
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- 1Full access to 66 UI challenges across all levels
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- 1Full access to 66 UI challenges across all levels
- 2Full access to 95 katas across all levels
- 3Full access to 675 quiz questions
- 4Unlimited quizzes
- 5New challenges added every week
- 1Full access to 66 UI challenges across all levels
- 2Full access to 95 katas across all levels
- 3Full access to 675 quiz questions
- 4Unlimited quizzes
- 5New challenges added every week
- 1Start solving 18 free challenges and 42 free katas
- 2Free quiz questions to test your React knowledge
- 3Free playground to experiment with React, TypeScript and Tailwind
- 4All challenges include TypeScript and pre-styled layouts
- 5Code editor with optional Vim mode
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