获取“未捕获的 TypeError:无法读取未定义的属性(读取'Items')”

Getting " Uncaught TypeError: Cannot read properties of undefined (reading 'Items')"

提问人:Lax1177 提问时间:4/26/2022 最后编辑:Ted LyngmoLax1177 更新时间:4/26/2022 访问量:1745

问:

我在我正在处理的 react 项目上遇到此错误“Expenses.js:8 未捕获的 TypeError:无法读取未定义的属性(读取'Items')”,我不确定为什么我一直得到它。我是 REACT 的新手。非常感谢任何帮助

这是我的文件代码

App.js

import Expenses from "./components/Expenses";
 function App() {
  const expenses = [
    {
      id: "e1",
      title: "Toilet Paper",
      amount: 94.12,
      date: new Date(2020, 7, 14),
    },
    { id: "e2", title: "New TV", amount: 799.49, date: new Date(2021, 2, 12) },
    {
      id: "e3",
      title: "Car Insurance",
      amount: 294.67,
      date: new Date(2021, 2, 28),
    },
    {
      id: "e4",
      title: "New Desk (Wooden)",
      amount: 450,
      date: new Date(2021, 5, 12),
    },
  ];

  return (
    <div>
      <h2>Let's get started!</h2>
      <Expenses Items={expenses} />
    </div>
  );
}

export default App;

Expense.js

import ExpenseItem from "./ExpenseItem";
import "./Expenses.css";

function Expenses(props) {
  return (
    <div className="expenses">
      <ExpenseItem
        title={props.Items[0].title}
        amount={props.Items[0].amount}
        date={props.Items[0].date}
      />
      <ExpenseItem
        title={props.Items[1].title}
        amount={props.Items[1].amount}
        date={props.Items[1].date}
      />
      <ExpenseItem
        title={props.Items[2].title}
        amount={props.Items[2].amount}
        date={props.Items[2].date}
      />
      <ExpenseItem
        title={props.Items[3].title}
        amount={props.Items[3].amount}
        date={props.Items[3].date}
      />
    </div>
  );
}

export default Expenses();
JavaScript ReactJS TypeError UncaughtExceptionHandler

评论

0赞 R4ncid 4/26/2022
更改为export default Expenses();export default Expenses;

答:

2赞 R4ncid 4/26/2022 #1

要解决错误,您应该更改为export default Expenses();export default Expenses;

您还应该以这种方式重构代码

import ExpenseItem from "./ExpenseItem";
import "./Expenses.css";

function Expenses(props) {
  return (
    <div className="expenses">
      {props.Items.map((item, i) => <ExpenseItem
        key={i}
        title={item.title}
        amount={item.amount}
        date={item.date}
      />)}
    </div>
  );
}

export default Expenses;

-1赞 Lax1177 4/26/2022 #2

没关系。我找到了答案。

在我比较App.js和Expenses.js后,我发现我把Expenses.js的export default写错了(应该只是export default Expenses;

此问题已解决