when the parent component asynchronously obtains the data and passes it to the child component, but when the child component calls the data, it finds that the asynchronous data has not yet returned a result, and a undefined error is reported. Is there any solution
the reason for the analysis should be that when the child component accesses the props data, the asynchronous data of the parent component has not yet been returned, is it?
The code foris roughly as follows.
class ParentComponent extends React.Component {
constructor () {
// initial
}
componentDidMount () {
fetch("url").then(data => {
this.setState({
data: data,
);
})
}
render () {
renturn(
<ChildComponent data={this.state.data} />
);
}
}
class ChildComponent extends React.Component {
constructor () {
// initial
}
render () {
let { dataItem } = this.props.data; // Err: Cannot read property of undefined
console.log(this.props.data); // log empty arr first, then log full data /
}
}Thank you.