[Update element in react state array] #react

update_react_state_ex.js

// https://stackoverflow.com/a/46761122/1807163
const [employees, setEmployees] = useState([]);

const onUpdate((newEmployee) => {
  setEmployees((existingEmployees) => {
    const index = employees.findIndex(emp => emp.id === newEmployee.id);
	const newEmployees = [...existingEmployees]; // important to create a copy, otherwise you'll modify state outside of setState call
	newEemployees[index] = employee;
    return newEmployees;
  });  
}