Vue to react ----- can the constructor be omitted when using ES6?

class XXX extends Component {
constructor(props) {
super(props);
this.state = {
};
}

}
This way of writing is similar to

class XXX extends Component {
state = {
}
}

Is there any difference in writing ？ this Keywords are used normally

author ：Hull Qin
link ：https://www.zhihu.com/question/282019729/answer/1100603256
source ： You know
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If the subclass does not write a constructor, it will use the constructor of the parent class , Subclasses override the constructor of the parent class only when they want to have their own constructor , The subclass wants to have its own constructor and call the constructor of the parent class , Just use super. You can see the following example diagram 1 chart 2.

The two ways you say are really equivalent , Look at the picture 3.

chart 1、 No write constructor

chart 2、 Write constructor , But only the parent constructor is called