I'm really confused as to why I am receiving an undefined error in this code. Can someone please assist

I'm encountering an issue with getting undefined in this section of code. Is there a way to fetch the data using useEffect, and once everything is loaded, how can I efficiently store it in a useState variable and then display the necessary content?

const appDesign = require(`./data/${subcategory}`)

  useEffect(() => {if (router.asPath !== router.route) { }  }, [router])

Answer №1

I didn't have any prior experience with next.js

However, if you need to fetch data using useEffect(), and manage state within your component
start by declaring a state variable first

const [state, setState] = useState(0);

After that, load the data and update the state in the callback function of useEffect
for example:

useEffect(()=>{
  if (router) {
   // fetch some data or make an API request 
   // Then update the state
   let a = 1;
   setState(a);
  }
}, [router]);

For more information, please visit Using the State Hook

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