/Javascript/React/How to update a state with an array react

How to update a state with an array react

React how to update state array

const initialState = [
    { name: "foo", counter: 0 },
    { name: "far", counter: 0 },
    { name: "faz", counter: 0 }
  ];

const [state, setState] = useState(initialState);

const clickButton = () => {
	// 1. Make a shallow copy of the array
	let temp_state = [...state];
	
	// 2. Make a shallow copy of the element you want to mutate
	let temp_element = { ...temp_state[0] };
	
	// 3. Update the property you're interested in
	temp_element.counter = temp_element.counter+1;
	
	// 4. Put it back into our array. N.B. we *are* mutating the array here, but that's why we made a copy first
	temp_state[0] = temp_element;
	
	// 5. Set the state to our new copy
	setState( temp_state );
}

Source: stackoverflow.com

React native update state array of objects

let markers = [ ...this.state.markers ];
markers[index] = {...markers[index], key: value};
this.setState({ markers });

Source: stackoverflow.com

How to update a state with an array react

const [array, setArray] = useState([1, 2, 3])

// Add
setArray(prevArray => [...prevArray, 4]); // -> [1, 2, 3, 4]

// Remove last entry
setArray(prevArray => prevArray.splice(0, prevArray.length - 1)); // -> [1, 2, 3]

Similar codes

0 vote314 views1 answer
React-native-paper resize switch resize
Javascript React
33 votes329 views2 answers
UseRef react ref
Javascript React
0 vote324 views1 answer
Npm ERR! peer react@"^15.x.x" from [email protected]
Javascript React
0 vote336 views1 answer
How to go to settings on next click in react native
Javascript React
1 vote311 views1 answer
React construct
Javascript React
0 vote310 views1 answer
Javascript react useState update object
Javascript React
9 votes324 views2 answers
Axios react js
Javascript React
0 vote326 views1 answer
How to start react project on atom
Javascript React
0 vote359 views1 answer
How to change a react link icon when you send the link as message in whatsapp
Javascript React
4 votes309 views3 answers
Get params in react router dom v6
Javascript React