style={{backgroundColor:isHovering?'salmon':'',color:isHovering?'white':'',}}onMouseEnter={handleMouseEnter}onMouseLeave={handleMouseLeave}>Hover me</div> 三元运算符和if/else运算符非常的相似。 它检查问号左边的值是否为真值,如果是,操作符
setState: a function for setting a new value for your state. Similar to this.setState({name: newValue})(定义更改状态的函数或直接返回状态的值,组件状态值改变,就会触发re-render) initialState 参数,则是初始化 state 状态的默认值(可以通过函数的形式返回值)。 基于以上基础知识后,我们来改下第三部分...
accept: 必填，支持字符串或者字符串数组，对应于drag的type值，同样的值才可被拖入此元素中 hover: 选...
Radium,jsxstyle,react-style 属于这一类。优点是能给 CSS 提供 JS 同样强大的模块化能力;缺点是不能利用成熟的 CSS 预处理器(或后处理器) Sass/Less/PostCSS,`:hover` 和 `:active` 伪类处理起来复杂。另一类是依旧使用 CSS,但使用 JS 来管理样式依赖,代表是 CSS Modules。CSS Modules 能最大化地结合现有 ...
This is where we can see what a Virtual DOM object actually is: a plain JavaScript Object that represents the tag to be rendered onto the screen. Let’s inspect the output of React.createElement(): console.log(<div/>) // or console.log(React.createElement('div', null)) This gives us...
import React from 'react'; import Style from 'style-it'; class Intro extends React.Component { render() { return Style.it(` #heart { position: relative; width: 100px; height: 90px; } #heart:before, #heart:after { position: absolute; content: ""; left: 50px; top: 0; width: 50...
Doing so, often requires tests likethis.state.hover && "hoverStyle"to applyhoverStyleonly ifthis.state.hoveris actuallytrue. React Inline Stylemakes this easier by reintroducing :pseudo classes. When applying a style class throughthis.style(), you can add any pseudo:variableNameto it. Doing so...
yt-lite:hover > .lty-playbtn { opacity: 1; } /* play button triangle */ .yt-lite > .lty-playbtn:before { content: ''; border-style: solid; border-width: 11px 0 11px 19px; border-color: transparent transparent transparent #fff; } .yt-lite > .lty-playbtn, .yt-lite > .lty...
components/Book.js create mode 100644 src/components/BookForm.js create mode 100644 src/components/BooksList.js create mode 100644 src/components/EditBook.js create mode 100644 src/components/Header.js create mode 100644 src/context/BooksContext.js create mode 100644 src/hooks/useLocalStorage.js ...
Style import # CSS @import "react-alice-carousel/lib/alice-carousel.css"; # SCSS @import "react-alice-carousel/lib/scss/alice-carousel.scss"; Usage importReactfrom'react';importAliceCarouselfrom'react-alice-carousel';import'react-alice-carousel/lib/alice-carousel.css';consthandleDragStart=(e)=...