as shown in the figure, what does the this.props stand for here? is it a calling method?
as shown in the figure, what does the this.props stand for here? is it a calling method?
is an object passed from the parent component, in which there are values, methods, and many things
this is the method passed down from the parent component, which is defined in the parent component. Pass the required data in the child component to
get the value passed from the parent component
<Parents>
<child data={a:1}/>
</Parents>
// child.js
child.js this.props.data = {a: 1} Previous: The check box defaults to the selected question.
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like this [array [xxx], array [xxx], array [xxx].] merge all xxx in array into one array [xxx.] ...