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  • Medium

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Last updated on 11/8/22

Manage Data in a React App Using State and Effects

Evaluated skills

  • Manage data in a React app using state and effects
  • Question 1

    Which of these statements is incorrect?

    • Local state exists within a component.

    • However many times this component re-renders, the data will be preserved.

    • Use local state in a function component with useState.

    • Update state with   useState(newValue) .

  • Question 2

    You want to create a  cartValue  local state set to 0 that will let you save the price of items added to the cart. 

    Which syntaxes could you use to get and update your state?

    Careful, there are several correct answers.
    • const updateCartValue = useState({ cartValue: 0 })
      
    • const cartState = useState(0)
      const cartValue = cartState[0]
      const updateCartValue = cartState[1]
      
    • const [cartValue, updateCartValue] = useState(0)
      
    • const [cartValue, updateCartValue] = useState(1)
      
  • Question 3

    Which of these statements are true?

    Careful, there are several correct answers.
    • useEffect  and  useState  have to be imported from the package "react-hooks."

    • useEffect  and  useState  are the only two hooks that exist.

    • Hooks didn’t exist when React was first created.

    • A hook is a function that allows us to hook into React functionalities.

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