Add item into array if it does not exist otherwise delete it
import React from 'react';
class PushOrSpliceArray extends React.Component {
state = {array: []}
addItemArray = (item) => {
var newArray = [...this.state.array]
var indexItem = newArray.indexOf(item)
indexItem === -1 ? newArray.push(item) : newArray.splice(item, 1);
this.setState({ array: newArray });
}
}