State is used for properties on a component that will change, versus static properties that are passed in. This lesson will introduce you to taking input within your React components. Unlike props, which are meant to be passed into our component as s…

State is used for properties on a component that will change, versus static properties that are passed in. This lesson will introduce you to taking input within your React components. Properties vs. State When you think of properties, you should be t…

react 中state与props 1.state与props props是只读属性,只有在组件被实例化的时候可以赋值,之后的任何时候都无法改变该值.如果试图修改该值时,控制台会报错 only read. state与props正好相反,state中保存可变的值.通过this.setState()方法修改对应的值.使用state必须通过es6继承React.Component 类(官方推荐写法),并在构造函数内进行初始化. export default class BoubleBind ext…

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 evolvefunction to make our updater function a reusable utility that isn't tied to the React A…

如果你看过React的官方文档,就会对怎么给局部state赋值有一定的了解.如下代码: class Test extends React.Component { constructor(props) { super(props); this.state = { name:'李磊' }; // 为了在回调中使用 `this`,这个绑定是必不可少的 this.handleClick = this.handleClick.bind(this); } handleClick(){ this.setSta…

在学习React的组件的时候,我也好奇组件间需要共享状态或通信的时候,React是如何处理的.在文档的QUICK START的提到Lifting State Up(状态提升),并不是什么新鲜东西.只是把几个组件需要共享的状态拿出来放到最近的父组件而已.然后通过传参的方式注入子组件,成为其props.由于子组件获取的状态state_inShare都来自父组件,因此各自的state_inShare是同步的. In React, sharing state is accomplished by mov…

Recoil & React official state management Redux Recoil.js https://recoiljs.org/ A state management library for React $ npx create-react-app my-app $ npm init react-app my-app $ yarn create react-app my-app $ yarn add recoil https://github.com/facebook…

React & update state with props & Object.assign Object.assign({}, oldObj, newObj) https://reactjs.org/docs/react-component.html#unsafe_componentwillreceiveprops Object.assign( previousState, {quantity: state.quantity + 1}, {quantity: state.quantit…

state&事件处理&ref 在 react 起步 一文中,我们学习了 react 相关知识:jsx.组件.props.本篇将继续研究 state.事件处理和ref. state State 与 props 类似,但是 state 是私有的,并且完全受控于当前组件 -- 官网 react 中的 props 用来接收父组件传来的属性,并且是只读的. 由此,我们能猜测 state 就是组件自身属性. Tip:是否感觉像 vue 组件中的 data,请接着看! var app = new Vue…

React components have a lifecycle, and you are able to access specific phases of that lifecycle. This lesson will introduce mounting and unmounting of your React components. import React from 'react'; import ReactDOM from 'react-dom'; export default…