1this.setState(prevState => ({
2  myArray: [...prevState.myArray, "new value"]
3}))
4

1setTheArray([...theArray, newElement]);

1how to add array data on state react
2this.setState({ myArray: [...this.state.myArray, 'new value'] }) //simple value
3this.setState({ myArray: [...this.state.myArray, ...[1,2,3] ] }) //another array

1this.setState({ myArray: [...this.state.myArray, 'new value'] }) //simple value
2this.setState({ myArray: [...this.state.myArray, ...[1,2,3] ] }) //another array
3

1setArray(oldArray => [...oldArray,newValue] );
2

1const initialState = [
2    { name: "foo", counter: 0 },
3    { name: "far", counter: 0 },
4    { name: "faz", counter: 0 }
5  ];
6
7const [state, setState] = useState(initialState);
8
9const clickButton = () => {
10	// 1. Make a shallow copy of the array
11	let temp_state = [...state];
12	
13	// 2. Make a shallow copy of the element you want to mutate
14	let temp_element = { ...temp_state[0] };
15	
16	// 3. Update the property you're interested in
17	temp_element.counter = temp_element.counter+1;
18	
19	// 4. Put it back into our array. N.B. we *are* mutating the array here, but that's why we made a copy first
20	temp_state[0] = temp_element;
21	
22	// 5. Set the state to our new copy
23	setState( temp_state );
24}