如何在ReactJS中获得视口高度?在正常的JavaScript中使用

window.innerHeight()

但是使用ReactJS,我不确定如何获得这些信息。我的理解是

ReactDOM.findDomNode()

仅适用于已创建的组件。然而,对于文档或body元素,情况并非如此,它们可以为我提供窗口的高度。


当前回答

这是你如何实现它,并在React函数组件中实时获得窗口宽度和高度:

import React, {useState, useEffect} from 'react' 
const Component = () => {
  const [windowWidth, setWindowWidth] = useState(0)
  const [windowHeight, setWindowHeight] = useState(0)
  
  useEffect(() => {
    window.addEventListener('resize', e => {
      setWindowWidth(window.innerWidth);
    });
  }, [window.innerWidth]);

  useEffect(() => {
    window.addEventListener('resize', e => {
      setWindowHeight(window.innerHeight);
    });
  }, [window.innerHeight]);

  return(
    <h3>Window width is: {windowWidth} and Height: {windowHeight}</h3>
  )
}

其他回答

我刚刚编辑了QoP当前的答案以支持SSR,并将其与Next.js (React 16.8.0+)一起使用:

/钩/ useWindowDimensions.js:

import { useState, useEffect } from 'react';

export default function useWindowDimensions() {

  const hasWindow = typeof window !== 'undefined';

  function getWindowDimensions() {
    const width = hasWindow ? window.innerWidth : null;
    const height = hasWindow ? window.innerHeight : null;
    return {
      width,
      height,
    };
  }

  const [windowDimensions, setWindowDimensions] = useState(getWindowDimensions());

  useEffect(() => {
    if (hasWindow) {
      function handleResize() {
        setWindowDimensions(getWindowDimensions());
      }

      window.addEventListener('resize', handleResize);
      return () => window.removeEventListener('resize', handleResize);
    }
  }, [hasWindow]);

  return windowDimensions;
}

/ yourComponent.js:

import useWindowDimensions from './hooks/useWindowDimensions';

const Component = () => {
  const { height, width } = useWindowDimensions();
  /* you can also use default values or alias to use only one prop: */
  // const { height: windowHeight = 480 } useWindowDimensions();

  return (
    <div>
      width: {width} ~ height: {height}
    </div>
  );
}

你可以像这样创建自定义钩子:

import { useEffect, useState } from "react";
import { debounce } from "lodash";

const getWindowDimensions = () => {
  const { innerWidth: width, innerHeight: height } = window;
  return { width, height };
};

export function useWindowSize(delay = 0) {
  const [windowDimensions, setWindowDimensions] = useState(
    getWindowDimensions()
  );

  useEffect(() => {
    function handleResize() {
      setWindowDimensions(getWindowDimensions());
    }
    const debouncedHandleResize = debounce(handleResize, delay);
    window.addEventListener("resize", debouncedHandleResize);
    return () => window.removeEventListener("resize", debouncedHandleResize);
  }, [delay]);

  return windowDimensions;
}

我刚刚花了一些认真的时间用React和滚动事件/位置来解决一些问题-所以对于那些仍然在寻找的人,这里是我发现的:

视口高度可以通过使用window来找到。innerHeight或使用document.documentElement.clientHeight。(当前视口高度)

整个文档(主体)的高度可以使用window.document.body.offsetHeight找到。

如果你试图找到文档的高度,并知道什么时候你已经触底了——下面是我想到的:

if (window.pageYOffset >= this.myRefII.current.clientHeight && Math.round((document.documentElement.scrollTop + window.innerHeight)) < document.documentElement.scrollHeight - 72) {
        this.setState({
            trueOrNot: true
        });
      } else {
        this.setState({
            trueOrNot: false
        });
      }
    }

(我的导航条在固定位置是72px,因此-72得到一个更好的滚动事件触发器)

最后,这里有一些到console.log()的滚动命令,这些命令帮助我积极地计算数学。

console.log('window inner height: ', window.innerHeight);

console.log('document Element client hieght: ', document.documentElement.clientHeight);

console.log('document Element scroll hieght: ', document.documentElement.scrollHeight);

console.log('document Element offset height: ', document.documentElement.offsetHeight);

console.log('document element scrolltop: ', document.documentElement.scrollTop);

console.log('window page Y Offset: ', window.pageYOffset);

console.log('window document body offsetheight: ', window.document.body.offsetHeight);

唷!希望它能帮助到一些人!

用一点打字稿

import { useState, useEffect } from 'react'; interface WindowDimentions { width: number; height: number; } function getWindowDimensions(): WindowDimentions { const { innerWidth: width, innerHeight: height } = window; return { width, height }; } export default function useWindowDimensions(): WindowDimentions { const [windowDimensions, setWindowDimensions] = useState<WindowDimentions>( getWindowDimensions() ); useEffect(() => { function handleResize(): void { setWindowDimensions(getWindowDimensions()); } window.addEventListener('resize', handleResize); return (): void => window.removeEventListener('resize', handleResize); }, []); return windowDimensions; }

保持当前尺寸状态的简单方法,即使在窗口调整大小后:

//set up defaults on page mount
componentDidMount() {
  this.state = { width: 0, height: 0 };
  this.getDimensions(); 

  //add dimensions listener for window resizing
  window.addEventListener('resize', this.getDimensions); 
}

//remove listener on page exit
componentWillUnmount() {
  window.removeEventListener('resize', this.getDimensions); 
}

//actually set the state to the window dimensions
getDimensions = () => {
  this.setState({ width: window.innerWidth, height: window.innerHeight });
  console.log(this.state);
}