I have this error when I'm running npm start on my project. I know this is because a variable is not declared before it's called (I think) but I can't manage to make it work.
[image with the error] : https://i.stack.imgur.com/VBya2.png
TypeError: Cannot read properties of undefined (reading 'total')
Code:
import React from 'react';
import millify from 'millify';
import { Typography, Row, Col, Statistic } from 'antd';
import { Link } from 'react-router-dom';
import { useGetCryptosQuery } from '../services/cryptoApi';
import Cryptocurrencies from './Cryptocurrencies';
import News from './News';
import Loader from './Loader';
const { Title } = Typography;
const Homepage = () => {
const { data, isFetching } = useGetCryptosQuery(10);
const globalStats = data?.data?.stats;
if (isFetching) return <Loader />;
return (
<>
<Title level={2} className="heading">Global Crypto Stats</Title>
<Row gutter={[32, 32]}>
<Col span={12}><Statistic title="Total Cryptocurrencies" value={globalStats.total} /></Col>
<Col span={12}><Statistic title="Total Exchanges" value={millify(globalStats.totalExchanges)} /></Col>
<Col span={12}><Statistic title="Total Market Cap:" value={`$${millify(globalStats.totalMarketCap)}`} /></Col>
<Col span={12}><Statistic title="Total 24h Volume" value={`$${millify(globalStats.total24hVolume)}`} /></Col>
<Col span={12}><Statistic title="Total Cryptocurrencies" value={globalStats.total} /></Col>
<Col span={12}><Statistic title="Total Markets" value={millify(globalStats.totalMarkets)} /></Col>
</Row>
<div className="home-heading-container">
<Title level={2} className="home-title">Top 10 Cryptos In The World</Title>
<Title level={3} className="show-more"><Link to="/cryptocurrencies">Show more</Link></Title>
</div>
<Cryptocurrencies simplified />
<div className="home-heading-container">
<Title level={2} className="home-title">Latest Crypto News</Title>
<Title level={3}><Link to="/news">Show more</Link></Title>
</div>
<News simplified />
</>
);
};
export default Homepage;
Thank you for your time!!
CodePudding user response:
You have 2 choices, first, you can display the component conditionally like :
{globalStats && (
<Component>
</Component>
)}
Or, you can just put default values like :
// First solution (better one)
value={globalStats?.total}
// Second solution (Not that good, but working)
value={globalStats.total || 0}