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

添加这个是为了多样性和干净的方法。

此代码使用函数式方法。我已经使用onresize而不是addEventListener,如在其他答案中提到的。

import { useState, useEffect } from "react";

export default function App() {
  const [size, setSize] = useState({
    x: window.innerWidth,
    y: window.innerHeight
  });
  const updateSize = () =>
    setSize({
      x: window.innerWidth,
      y: window.innerHeight
    });
  useEffect(() => (window.onresize = updateSize), []);
  return (
    <>
      <p>width is : {size.x}</p>
      <p>height is : {size.y}</p>
    </>
  );
}

其他回答

class AppComponent extends React.Component {

  constructor(props) {
    super(props);
    this.state = {height: props.height};
  }

  componentWillMount(){
    this.setState({height: window.innerHeight + 'px'});
  }

  render() {
    // render your component...
  }
}

设置道具

AppComponent.propTypes = {
 height:React.PropTypes.string
};

AppComponent.defaultProps = {
 height:'500px'
};

视口高度现在可用{this.state。渲染模板中的Height}

使用useEffect很简单

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

使用钩子:

使用useLayoutEffect在这里更有效:

import { useState, useLayoutEffect } from 'react';

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

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

  useLayoutEffect(() => {
    function handleResize() {
      setWindowDimensions(getWindowDimensions());
    }

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

  return windowDimensions;
}

用法:

const { height, width } = useWindowDimensions();

这个答案与Jabran Saeed的类似,除了它也处理窗口大小的调整。接下来交给我吧。

constructor(props) {
  super(props);
  this.state = { width: 0, height: 0 };
  this.updateWindowDimensions = this.updateWindowDimensions.bind(this);
}

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

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

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

通过在useCallback中包装getWindowDimensions函数,我对代码进行了轻微的更新

import { useCallback, useLayoutEffect, useState } from 'react';

export default function useWindowDimensions() {

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

    const getWindowDimensions = useCallback(() => {
        const windowWidth = hasWindow ? window.innerWidth : null;
        const windowHeight = hasWindow ? window.innerHeight : null;

        return {
            windowWidth,
            windowHeight,
        };
    }, [hasWindow]);

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

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

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

    return windowDimensions;
}