在我的Next.js应用程序中,我似乎无法访问窗口:
未处理的拒绝(ReferenceError):没有定义窗口
componentWillMount() {
console.log('window.innerHeight', window.innerHeight);
}
在我的Next.js应用程序中,我似乎无法访问窗口:
未处理的拒绝(ReferenceError):没有定义窗口
componentWillMount() {
console.log('window.innerHeight', window.innerHeight);
}
当前回答
我在一个自定义钩子中包装了一般的解决方案(if (typeof window === 'undefined')返回;),这让我非常满意。它有一个类似的界面来反应useMemo钩子,我真的很喜欢。
import { useEffect, useMemo, useState } from "react";
const InitialState = Symbol("initial");
/**
*
* @param clientFactory Factory function similiar to `useMemo`. However, this function is only ever called on the client and will transform any returned promises into their resolved values.
* @param deps Factory function dependencies, just like in `useMemo`.
* @param serverFactory Factory function that may be called server side. Unlike the `clientFactory` function a resulting `Promise` will not be resolved, and will continue to be returned while the `clientFactory` is pending.
*/
export function useClientSideMemo<T = any, K = T>(
clientFactory: () => T | Promise<T>,
deps: Parameters<typeof useMemo>["1"],
serverFactory?: () => K
) {
const [memoized, setMemoized] = useState<T | typeof InitialState>(
InitialState
);
useEffect(() => {
(async () => {
setMemoized(await clientFactory());
})();
// eslint-disable-next-line react-hooks/exhaustive-deps
}, deps);
return typeof window === "undefined" || memoized === InitialState
? serverFactory?.()
: memoized;
}
使用的例子:
我使用它来动态导入与next.js中的SSR不兼容的库,因为它自己的动态导入只与组件兼容。
const renderer = useClientSideMemo(
async () =>
(await import("@/components/table/renderers/HighlightTextRenderer"))
.HighlightTextRendererAlias,
[],
() => "text"
);
正如你所看到的,我甚至实现了一个回退工厂回调,所以你可以提供一个结果时,最初呈现在服务器上。在所有其他方面,这个钩子应该表现类似于react useMemo钩子。接受反馈。
其他回答
在类Component的构造函数中可以添加
if (typeof window === 'undefined') {
global.window = {}
}
例子:
import React, { Component } from 'react'
class MyClassName extends Component {
constructor(props){
super(props)
...
if (typeof window === 'undefined') {
global.window = {}
}
}
这将避免错误(在我的例子中,错误将在我单击重载页面后发生)。
在刷新页面时,我也遇到了同样的问题(由于导入与SSR不能很好地工作)。
对我来说,固定它的是去发生这种情况的页面,并迫使导入是动态的:
import dynamic from 'next/dynamic';
const SomeComponent = dynamic(()=>{return import('../Components/SomeComponent')}, {ssr: false});
//import SomeComponent from '../Components/SomeComponent'
注释掉原始导入并动态导入组件将强制组件的客户端呈现。
动态导入在Nextjs的文档中有介绍: https://nextjs.org/docs/advanced-features/dynamic-import
我通过观看youtube视频找到了这个解决方案: https://www.youtube.com/watch?v=DA0ie1RPP6g
我必须从URL访问哈希,所以我想到了这个
const hash = global.window && window.location.hash;
没有SSR
https://nextjs.org/docs/advanced-features/dynamic-import#with-no-ssr
import dynamic from 'next/dynamic'
const DynamicComponentWithNoSSR = dynamic(
() => import('../components/hello3'),
{ ssr: false }
)
function Home() {
return (
<div>
<Header />
<DynamicComponentWithNoSSR />
<p>HOME PAGE is here!</p>
</div>
)
}
export default Home
发生错误是因为窗口尚未可用,而组件仍在挂载。组件挂载后,可以访问窗口对象。
您可以创建一个非常有用的钩子来获取动态窗口。innerHeight或window.innerWidth
const useDeviceSize = () => {
const [width, setWidth] = useState(0)
const [height, setHeight] = useState(0)
const handleWindowResize = () => {
setWidth(window.innerWidth);
setHeight(window.innerHeight);
}
useEffect(() => {
// component is mounted and window is available
handleWindowResize();
window.addEventListener('resize', handleWindowResize);
// unsubscribe from the event on component unmount
return () => window.removeEventListener('resize', handleWindowResize);
}, []);
return [width, height]
}
export default useDeviceSize
用例:
const [width, height] = useDeviceSize();