Event handlers in React
React interview exercise on Components & JSX, difficulty 2 of 3. Solve it in the editor beside a worked example, or cold in Interview mode with the example hidden; the tests run the moment you do.
Write Toolbar with props `onAction(name)` and `canDelete` (default false): a <button className="save">Save</button> that calls onAction("save") and a <button className="delete">Delete</button> that calls onAction("delete") and is disabled unless canDelete. Nothing may be called while rendering.
Each exercise pairs a worked example with a twin problem to solve in a real editor; the tests run the moment you do. Interview mode hides the example: solve it from memory, without the hint or the solution, and it counts as solved cold. Progress is saved in your browser, and in your account if you sign in.