setState with variable react es6

Question

I'm new here in reactjs, i'm using react-bootstrap for my UI. Now, I encounter a script where in a setState is the value of a variable and pass it on the onHide of the modal. Im not sure what to search to find an answer that's why I posted a question here.

let closeBoardAddModal = () => this.setState({ boardAddModalShow: false })
<BoardAddModal show={this.state.boardAddModalShow} onHide={closeBoardAddModal} />

Answer 1

let closeBoardAddModal = () => this.setState({ boardAddModalShow: false })

In the above stament closeBoardModal is not a value but is a function. This the ES6 syntax where () will contain the arguments and anything after => will be the body of the function. This syntax also the binding operation for you.

The above syntax is equivalent to

closeBoardAddModal() {
    this.setState({ boardAddModalShow: false });
}.bind(this);

So in the below code

<BoardAddModal show={this.state.boardAddModalShow} onHide={closeBoardAddModal} />

when you do onHide={closeBoardAddModal} it will call the function closeBoardAddModal on an onHide event which internally the sets the state boardAddModalShow to false.