to render a list. The parent component passes down a data. The
subcomponent is received, and the thumbnail field of data is used.
but there is a thumbnail field of data that is null. Makes it impossible to render.
can you assign it a default value?
ask for advice. Please know how to operate and give me some advice. Thank you.
this requires the use of smart components, that is, class components. You can specify the initial value of props .
class Demo extends Component {
static defaultProps {
// props
}
}class Demo extends Component {
// something
}
Demo.defaultProps = {
// default props
}Previous: Ask for help with sql?
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