标签:import tle with cto xtend increase from component factor
In this lesson we‘ll take a stateful React component and look at how we can refactor our setState
calls to use an updater function and then leverage Ramda‘s evolve
function to make our updater function a reusable utility that isn‘t tied to the React API.
//@flow import React from ‘react‘; import {inc, dec, lensProp, over, evolve, multiply} from ‘ramda‘; // Using Lense const countLens = lensProp(‘count‘); const increase = over(countLens, inc); const decrease = over(countLens, dec); const doubleCount = evolve({count: multiply(2)}); export default class Counter extends React.Component { state = { count: 0 }; increase = () => this.setState(increase); decrease = () => this.setState(decrease); double = () => this.setState(doubleCount); render() { return ( <div> <button onClick={this.increase}>+</button> {this.state.count} <button onClick={this.decrease}>-</button> <button disabled={this.state.count === 0} onClick={this.double} >*2</button> </div> ); } }
[React] Update State in React with Ramda's Evolve
标签:import tle with cto xtend increase from component factor
原文地址:http://www.cnblogs.com/Answer1215/p/6741676.html