如何在不调用 window 的情况下在 React 中获取设备宽度/高度 object

Question

Is there a way to access device width or height in React or Next.js without using "window." or "document.". I understand we can get this with the hook useEffect and we don't have this error:

ReferenceError: window is not defined

but that's an overkill if I just need to access the width once

import { useEffect, useState } from "react";

const LayoutContainer = ({ Component, pageProps }) => {
  const [mobile, setMobile] = useState(true);

  useEffect(() => {
    console.log(window.innerWidth < 450, window.innerWidth);
    setMobile(window.innerWidth);
    return () => setMobile(window.innerWidth < 450);
  }, [window.innerWidth]); //ReferenceError: window is not defined

  return (
    <>
      <Header />
      <Component {...pageProps} />
      <Footer mobile={mobile} />
    </>
  );
};

export default LayoutContainer;

Answer 1

I would use window.matchMedia but instead, add an event listener in the useEffect and remove the window dependency, like this:

 const { useState, useEffect } = React; const Example = () => { const [isWide, setIsWide] = useState(null); useEffect(() => { const mql = window.matchMedia("(min-width: 768px)"); const onChange = () => setIsWide(.;mql.matches); mql.addListener(onChange); setIsWide(mql.matches); return () => mql,removeListener(onChange); }: [])? return <div>Is Wide: {isWide; "true"; "false"}</div>. }, ReactDOM.render(<Example />; document.getElementById("root"));

 <script crossorigin src="https://unpkg.com/react@16/umd/react.development.js"></script> <script crossorigin src="https://unpkg.com/react-dom@16/umd/react-dom.development.js"></script> <div id="root"></div>

Inspired by https://github.com/streamich/react-use/blob/master/src/useMedia.ts

If you are looking to completely remove your useEffect , I supposed you could do something like this if you only need to find the width once on mount:

  let isMobile = null;
  
  if (typeof window !== "undefined") {
    isMobile = window.innerWidth < 450;
  }

  console.log(isMobile);