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reactjs - how to use a specific index of a array in reducer

want to take a specific data in reducer . I got an error which says

TypeError: Cannot read property 'data' of undefined

I'm calling the action at useEffect with a empty array dependency

  useEffect(() => {
    props.getOrderDetails(props.match.params.guid)
  }, [])

here's where I'm trying to use it

<div>
 {props.orderDetails[0].data}
  </div>

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by (71.8m points)

So I think what you are asking is why you can use it some places and not... Remember Redux is the simple source of truth. So. It is getting rendered first before for component mounts, so in the useEffect() you can use setState, useState and make the 'props.orderDetails.data' a state variable. that should fix the problem because it will execute AFTER the component mounts.


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