Discussion on: Window not defined

[Sylvie Fiquet]

I don't get what your point is, are you asking for help?

It's normal to get an error, window is not defined on the server. Remember that Next runs your code on the server when building the HTML file.

Initialise your state to 0 and update it to window.innerWidth in useEffect.

[Jishnu-02]

can u show me how to do it?

[Sylvie Fiquet]

Something like that:

const [windowWidth, setWindowWidth] = useState(0)

// runs only once, on mount
useEffect(() => {
  if (window !== undefined){
    setWindowWidth(window.innerWidth)
    window.addEventListener('resize', handleWindowWidth)
  }
}, [])

[Jishnu-02]

Thank You.