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

我发现了一个简单的组合QoP和speckledcarp的答案,使用React Hooks和调整大小功能,代码行数略少:

const [width, setWidth]   = useState(window.innerWidth);
const [height, setHeight] = useState(window.innerHeight);
const updateDimensions = () => {
    setWidth(window.innerWidth);
    setHeight(window.innerHeight);
}
useEffect(() => {
    window.addEventListener("resize", updateDimensions);
    return () => window.removeEventListener("resize", updateDimensions);
}, []);

哦,是的,确保resize事件是双引号,而不是单引号。这一点让我有点不安;)

其他回答

我建议使用useSyncExternalStore

import { useSyncExternalStore } from "react";

const store = {
  size: {
    height: undefined,
    width: undefined
  }
};

export default function ChatIndicator() {
  const { height, width } = useSyncExternalStore(subscribe, getSnapshot);
  return (
    <h1>
      {width} {height}
    </h1>
  );
}

function getSnapshot() {
  if (
    store.size.height !== window.innerHeight ||
    store.size.width !== window.innerWidth
  ) {
    store.size = { height: window.innerHeight, width: window.innerWidth };
  }
  return store.size;
}

function subscribe(callback) {
  window.addEventListener("resize", callback);
  return () => {
    window.removeEventListener("resize", callback);
  };
}

如果你想试试:https://codesandbox.io/s/vibrant-antonelli-5cecpm

React原生web有一个useWindowDimensions钩子,可以使用:

    import { useWindowDimensions } from "react-native";
    const dimensions = useWindowDimensions()

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;
}

在这里,您可以将投票次数最多的答案包装在一个节点包中(已测试,typescript),以便使用。

安装:

npm i @teambit/toolbox.react.hooks.get-window-dimensions

用法:

import React from 'react';
import { useWindowDimensions } from '@teambit/toolbox.react.hooks.get-window-dimensions';

const MyComponent = () => {
  const { height, width } = useWindowDimensions();

  return (
    <>
      <h1>Window size</h1>
      <p>Height: {height}</p>
      <p>Width: {width}</p>
    </>
  );
};

使用钩子(React 16.8.0+)

创建一个useWindowDimensions钩子。

import { useState, useEffect } from 'react';

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

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

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

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

  return windowDimensions;
}

之后你就可以像这样在元件中使用它了

const Component = () => {
  const { height, width } = useWindowDimensions();

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

工作示例

原来的答案

在React中也是一样的,你可以使用window。innerHeight来获取当前视口的高度。

正如你在这里看到的