React挂钩2020:)

import React, { useLayoutEffect } from 'react';
import { useLocation } from 'react-router-dom';

const ScrollToTop: React.FC = () => {
  const { pathname } = useLocation();
  useLayoutEffect(() => {
    window.scrollTo(0, 0);
  }, [pathname]);

  return null;
};

export default ScrollToTop;

我唯一的解决方案是在每个文件中添加一行代码，例如:

import React from 'react';
const file = () => { document.body.scrollTop = 0; return( <div></div> ) }

但是课程太2018年了

ScrollToTop实现与React挂钩

ScrollToTop.js

import { useEffect } from 'react';
import { withRouter } from 'react-router-dom';

function ScrollToTop({ history }) {
  useEffect(() => {
    const unlisten = history.listen(() => {
      window.scrollTo(0, 0);
    });
    return () => {
      unlisten();
    }
  }, []);

  return (null);
}

export default withRouter(ScrollToTop);

用法:

<Router>
  <Fragment>
    <ScrollToTop />
    <Switch>
        <Route path="/" exact component={Home} />
    </Switch>
  </Fragment>
</Router>

ScrollToTop也可以实现为一个包装器组件:

ScrollToTop.js

import React, { useEffect, Fragment } from 'react';
import { withRouter } from 'react-router-dom';

function ScrollToTop({ history, children }) {
  useEffect(() => {
    const unlisten = history.listen(() => {
      window.scrollTo(0, 0);
    });
    return () => {
      unlisten();
    }
  }, []);

  return <Fragment>{children}</Fragment>;
}

export default withRouter(ScrollToTop);

用法:

<Router>
  <ScrollToTop>
    <Switch>
        <Route path="/" exact component={Home} />
    </Switch>
  </ScrollToTop>
</Router>

对于react-router v4，这里有一个实现滚动恢复的create-react-app: http://router-scroll-top.surge.sh/。

要实现这一点，你可以创建装饰Route组件和利用生命周期方法:

import React, { Component } from 'react';
import { Route, withRouter } from 'react-router-dom';

class ScrollToTopRoute extends Component {
  componentDidUpdate(prevProps) {
    if (this.props.path === this.props.location.pathname && this.props.location.pathname !== prevProps.location.pathname) {
      window.scrollTo(0, 0)
    }
  }

  render() {
    const { component: Component, ...rest } = this.props;

    return <Route {...rest} render={props => (<Component {...props} />)} />;
  }
}

export default withRouter(ScrollToTopRoute);

在componentDidUpdate上，我们可以检查位置路径名何时发生变化，并将其与路径道具匹配，如果满足，则恢复窗口滚动。

这个方法最酷的地方在于，我们可以有恢复滚动的路由和不恢复滚动的路由。

下面是一个App.js的例子，告诉你如何使用上面的方法:

import React, { Component } from 'react';
import { BrowserRouter as Router, Route, Link } from 'react-router-dom';
import Lorem from 'react-lorem-component';
import ScrollToTopRoute from './ScrollToTopRoute';
import './App.css';

const Home = () => (
  <div className="App-page">
    <h2>Home</h2>
    <Lorem count={12} seed={12} />
  </div>
);

const About = () => (
  <div className="App-page">
    <h2>About</h2>
    <Lorem count={30} seed={4} />
  </div>
);

const AnotherPage = () => (
  <div className="App-page">
    <h2>This is just Another Page</h2>
    <Lorem count={12} seed={45} />
  </div>
);

class App extends Component {
  render() {
    return (
      <Router>
        <div className="App">
          <div className="App-header">
            <ul className="App-nav">
              <li><Link to="/">Home</Link></li>
              <li><Link to="/about">About</Link></li>
              <li><Link to="/another-page">Another Page</Link></li>
            </ul>
          </div>
          <Route exact path="/" component={Home} />
          <ScrollToTopRoute path="/about" component={About} />
          <ScrollToTopRoute path="/another-page" component={AnotherPage} />
        </div>
      </Router>
    );
  }
}

export default App;

从上面的代码中，有趣的是，只有在导航到/关于或/另一个页面时，才会执行滚动到顶部的操作。然而，当进行/没有滚动恢复将发生。

整个代码库可以在这里找到:https://github.com/rizedr/react-router-scroll-top

我写了一个叫withScrollToTop的高阶组件。这个HOC有两个标志:

onComponentWillMount -导航时是否滚动到顶部(componentWillMount) onComponentDidUpdate—是否在更新时滚动到顶部(componentDidUpdate)。该标志在组件没有卸载但发生导航事件的情况下是必要的，例如，从/users/1到/users/2。

// @flow
import type { Location } from 'react-router-dom';
import type { ComponentType } from 'react';

import React, { Component } from 'react';
import { withRouter } from 'react-router-dom';

type Props = {
  location: Location,
};

type Options = {
  onComponentWillMount?: boolean,
  onComponentDidUpdate?: boolean,
};

const defaultOptions: Options = {
  onComponentWillMount: true,
  onComponentDidUpdate: true,
};

function scrollToTop() {
  window.scrollTo(0, 0);
}

const withScrollToTop = (WrappedComponent: ComponentType, options: Options = defaultOptions) => {
  return class withScrollToTopComponent extends Component<Props> {
    props: Props;

    componentWillMount() {
      if (options.onComponentWillMount) {
        scrollToTop();
      }
    }

    componentDidUpdate(prevProps: Props) {
      if (options.onComponentDidUpdate &&
        this.props.location.pathname !== prevProps.location.pathname) {
        scrollToTop();
      }
    }

    render() {
      return <WrappedComponent {...this.props} />;
    }
  };
};

export default (WrappedComponent: ComponentType, options?: Options) => {
  return withRouter(withScrollToTop(WrappedComponent, options));
};

使用它:

import withScrollToTop from './withScrollToTop';

function MyComponent() { ... }

export default withScrollToTop(MyComponent);

我的申请也遇到了同样的问题。使用下面的代码片段可以帮助我在单击下一个按钮时滚动到页面顶部。

<Router onUpdate={() => window.scrollTo(0, 0)} history= {browserHistory}>
...
</Router>

然而，在浏览器返回时，这个问题仍然存在。经过大量的尝试，我意识到这是因为浏览器窗口的历史对象，它有一个属性scrollRestoration被设置为auto。将此设置为手动解决了我的问题。

function scrollToTop() {
    window.scrollTo(0, 0)
    if ('scrollRestoration' in history) {
        history.scrollRestoration = 'manual';
    }
}

<Router onUpdate= {scrollToTop} history={browserHistory}>
....
</Router>