如何检查 react-router 是否在上下文中?

IT技术 angularjs reactjs react-router react-router-dom
2021-05-26 16:19:48

我正在一点一点地将一个 AngularJS 应用程序迁移到 React,我想要一个自定义的RouterLinkReact 组件来检查是否react-router在上下文中,以便它可以使用history,如果没有,则回退到使用 good old window.location但是我在react-router的文档中看不到任何检查方法

我尝试使用withRouter但它在不在上下文中时抛出并且ErrorBoundary似乎没有捕获错误。

有谁知道我该怎么做?

2个回答

react-router中公开了路由器上下文,即__RouterContext,通过使用它您可以检查路由器是否可用:

import React, { useContext } from 'react';
import { __RouterContext } from 'react-router';

const MyComponent = (props) => {
  const router = useContext(__RouterContext);

  if (router) {
    // Router context is avaible
  } else {
    // Use window.location as router context is not availble in this component
  }

  return <SomeOtherComponent />
}

只需将钩子包裹在一个try/catch

const {useState, useEffect, Fragment} = React;
const {useLocation, MemoryRouter} = ReactRouter;

const Cmp = () => {
  let loc;
  try {
    loc = useLocation();
  } catch (err) {
    return (
      <div>No Router Available</div>
    );
  }
  return (
    <div>Hello I can see {loc.pathname}</div>
  );
};

const App1 = () => {
  return (
    <Cmp/>
  );
};

const App2 = () => {
  return (
    <MemoryRouter>
      <Cmp/>
    </MemoryRouter>
  );
};

ReactDOM.render(<App1 />, document.getElementById("app1"));
ReactDOM.render(<App2 />, document.getElementById("app2"));
<script crossorigin src="https://unpkg.com/react@16/umd/react.production.min.js"></script>
<script crossorigin src="https://unpkg.com/react-dom@16/umd/react-dom.production.min.js"></script>
<script src="https://unpkg.com/react-router@5.1.2/umd/react-router.js"></script>

<div id="app1"></div>
<div id="app2"></div>