Analysis of React Routing principle

Rationale: After DOM rendering is complete, add the "Hashchange" event to the window to listen for changes to the page hash, and add the route attribute to the State property, which represents the route of the current page.

1, when clicked the Connection page hash change, triggers binds in the window the Hashchange event,

2. Change the route attribute in the state of the component in the Hashchange event (the page is automatically rendered when the State property of the react component changes)

3, the page with the state of the route attribute change automatically according to the constant hash to the child variable assignment of components, rendering

Core code:

import react from ' react ' import {render} from ' React-dom '


Const about = function () {return &L T div>111</div>} Const Inbox = function () {return < div>222</div>} Const HOME = function () {RET Urn < div>333</div>}
Class App extends react. Component {
state = {Route:window.location.hash. substr (1)}
Componentdidmount () {window. AddEventListener ( ' Hashchange ', () => {this. setstate ({route:window.location.hash. substr (1)})}
Render () {Let child switch (this.state.route) {case '/about ': a child = about; a break; a case '/inbox ': a child = a inbox; break; default:child = home;}
Return (< div> < h1>app Render (< App/>, document.body)