[Bug]: The solution to the state-related challenges on the webpage appear to be incorrect.
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- 主要语言
- JavaScript
- 星标
- 11.8k
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- 平均合并
- 1 天 11 小时
- 30 天内合并 PR
- 11
描述
Summary
In the documentation on the 'Learn' page, under the section 'Updating Arrays in State,' the solution for Challenge 2 appears to have a bug.
When using console.log to debug the solution, the counts in the product array do not match what is displayed on the screen.
Page
https://react.dev/learn/updating-arrays-in-state
Details
"According to the solution's description, when the '+' button is pressed, the count value in the initialProducts array should increment. However, logging the values to the console shows that the values on the screen differ from those in the array."
Solution with 2 extra lines for logging (App.js):
import { useState } from 'react';
const initialProducts = [{
id: 0,
name: 'Baklava',
count: 1,
}, {
id: 1,
name: 'Cheese',
count: 5,
}, {
id: 2,
name: 'Spaghetti',
count: 2,
}];
export default function ShoppingCart() {
const [
products,
setProducts
] = useState(initialProducts)
function handleIncreaseClick(productId) {
setProducts(products.map(product => {
if (product.id === productId) {
return {
...product,
count: product.count + 1
};
} else {
return product;
}
}))
// Next 2 lines are not parts of the solution.
// They were added to test the result.
console.log(initialProducts)
console.log(products)
}
function handleDecreaseClick(productId) {
let nextProducts = products.map(product => {
if (product.id === productId) {
return {
...product,
count: product.count - 1
};
} else {
return product;
}
});
nextProducts = nextProducts.filter(p =>
p.count > 0
);
setProducts(nextProducts)
}
return (
<ul>
{products.map(product => (
<li key={product.id}>
{product.name}
{' '}
(<b>{product.count}</b>)
<button onClick={() => {
handleIncreaseClick(product.id);
}}>
+
</button>
<button onClick={() => {
handleDecreaseClick(product.id);
}}>
–
</button>
</li>
))}
</ul>
);
}
贡献指南
从这里开始
- 先读完整个 Issue,再读项目的贡献指南。
- 在 Issue 下留言说明你要接手 —— 这能避免两个人做同样的事。
- Fork 仓库,在一个分支上完成修改。
- 提交 Pull Request,并在描述里引用这个 Issue 编号。
调研方向
打开 Updating Arrays in State 页面,使用提供的 App.js 示例重现 Challenge 2,并将控制台输出与渲染出的计数进行比较。确定解决方案或其解释是否不正确;当文档中的 challenge 产生一致的状态和显示结果时,即表示完成。
由索引模型根据 Issue 内容生成。
评估
- 技术栈
- javascript, react
- 领域
- documentation
- Issue 类型
- 缺陷
- 难度
- 2/5
- 预计耗时
- 1-3 小时
- 活跃度
- 停滞
- 描述清晰度
- 基本清楚
- 新手友好度
- 45/100