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

使用useEffect很简单

useEffect(() => {
    window.addEventListener("resize", () => {
        updateDimention({ 
            ...dimension, 
            width: window.innerWidth, 
            height: window.innerHeight 
        });
        console.log(dimension);
    })
})

其他回答

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);
}

有一个包有93.000+下载,名为useWindowSize()

NPM I @react-hook/window-size

import {
  useWindowSize,
  useWindowWidth,
  useWindowHeight,
} from '@react-hook/window-size'

const Component = (props) => {
  const [width, height] = useWindowSize()
  const onlyWidth = useWindowWidth()
  const onlyHeight = useWindowHeight()
...
}

docs

@speckledcarp的回答很好,但是如果你需要在多个组件中使用这个逻辑,那么可能会很乏味。您可以将其重构为HOC(高阶组件),以使此逻辑更易于重用。

withWindowDimensions.jsx

import React, { Component } from "react";

export default function withWindowDimensions(WrappedComponent) {
    return class extends Component {
        state = { width: 0, height: 0 };

        componentDidMount() {
            this.updateWindowDimensions();
            window.addEventListener("resize", this.updateWindowDimensions);
        }

        componentWillUnmount() {
            window.removeEventListener("resize", this.updateWindowDimensions);
        }

        updateWindowDimensions = () => {
            this.setState({ width: window.innerWidth, height: window.innerHeight });
        };

        render() {
            return (
                <WrappedComponent
                    {...this.props}
                    windowWidth={this.state.width}
                    windowHeight={this.state.height}
                    isMobileSized={this.state.width < 700}
                />
            );
        }
    };
}

然后在你的主组件中:

import withWindowDimensions from './withWindowDimensions.jsx';

class MyComponent extends Component {
  render(){
    if(this.props.isMobileSized) return <p>It's short</p>;
    else return <p>It's not short</p>;
}

export default withWindowDimensions(MyComponent);

你也可以“堆叠”hoc,如果你有另一个你需要使用,例如withthrouter (withWindowDimensions(MyComponent))

编辑:我现在会用React钩子(上面的例子),因为它们解决了hoc和类的一些高级问题

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>
  );
}

@foad abdollahi和@giovannipds答案的组合帮助我在Nextjs中使用useLayoutEffect自定义挂钩找到了一个解决方案。

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

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

    useLayoutEffect(() => {
      const isWindow = typeof window !== 'undefined';
      function handleResize() {
        setWindowDimensions(getWindowDimensions());
      }

      isWindow && window.addEventListener('resize', handleResize);
      console.log(windowDimensions);
      return () =>
        isWindow && window.removeEventListener('resize', handleResize);
    }, [windowDimensions]);

    return windowDimensions;
  }