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福建建设中心网站,排行榜,佛山网站制作哪里好,wordpress图片自动轮播插件React从入门到精通之购物车案例1. 购物车需求说明使用到的data list2. 项目code1. 购物车需求说明 list data展示到列表中每个item的通过按钮来控制购买的数据量删除按钮可以删除当前的itemTotal Price计算当前购物车的总的价格使用到的data list const books [{id: 1,name…

React从入门到精通之购物车案例

1. 购物车需求说明
- 使用到的data list
2. 项目code

1. 购物车需求说明

在这里插入图片描述

list data展示到列表中
每个item的通过±按钮来控制购买的数据量
删除按钮可以删除当前的item
Total Price计算当前购物车的总的价格

使用到的data list

const books = [{id: 1,name: 'introduction to algorithms',date: '2006-9',price: 85.00,count: 1},{id: 2,name: 'The Art of UNIX Programming',date: '2006-2',price: 59.00,count: 1},{id: 3,name: 'Programming pearls',date: '2008-10',price: 39.00,count: 1},{id: 4,name: 'Complete code',date: '2006-3',price: 128.00,count: 1},]

2. 项目code

<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><meta http-equiv="X-UA-Compatible" content="IE=edge"><meta name="viewport" content="width=device-width, initial-scale=1.0"><title>shop car demo</title><style>table {border-collapse: collapse;text-align: center;}thead {background-color: #f2f2f2;}td, th {padding: 10px 16px;border: 1px solid #aaa;        }</style>
</head>
<body><div id="root"></div><!-- import react dependencies --><script src="../../lib/react.js"></script><script src="../../lib/react-dom.js"></script><script src="../../lib/babel.js"></script><!-- import data --><script src="./data.js"></script><script type="text/babel">// component Appclass App extends React.Component {constructor(){super()this.state = {books: books}}// add sumincrement(index) {const newBooks = [...this.state.books]newBooks[index].count += 1this.setState({ books: newBooks })}// reduce sum decrement(index) {const newBooks = [...this.state.books]newBooks[index].count -= 1this.setState({ books: newBooks })}/*delte item from table*/deleteItem(index) {const newBooks = [...this.state.books]newBooks.splice(index, 1)this.setState({ books: newBooks })}render(){const { books } = this.statereturn (<div><table><thead><tr><td>Order</td><td>Name</td><td>Publish Date</td><td>Price</td><td>Bought Sum</td><td>Operation</td></tr></thead><tbody>{books.map((item, index) => {return (<tr key={ item.id }><td>{ index + 1 }</td><td>{ item.name }</td><td>{ item.date }</td><td>{ '$' + item.price }</td><td><button disabled={ item.count <=1 } onClick={ () => {this.decrement(index)} }>-</button>{ item.count }<button onClick={ () => {this.increment(index)} }>+</button></td><td><button onClick={ () => {this.deleteItem(index)} }>Delete</button></td></tr>)})}</tbody></table><h2>Total Price: $ {books.reduce((preValue, item) => preValue + item.count * item.price, 0)}</h2></div>)}}// create react domconst root = ReactDOM.createRoot(document.querySelector("#root"))// dom render by reactroot.render(<App/>)</script></body>
</html>