append to state array react code example

Example 1: how to add array data on state react

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

Example 2: how to update array in react state

this.setState(prevState => ({
  arrayvar: [...prevState.arrayvar, newelement]
}))

Example 3: add new array at the back of react state

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

Example 4: react native update state array of objects

let newMarkers = markers.map(el => (
      el.name==='name'? {...el, key: value}: el
))
this.setState({ markers });

Example 5: add new array at the back of react state

this.setState(prevState => ({
  myArray: [...prevState.myArray, {"name": "object"}]
}))

Example 6: add new array at the back of react state

this.setState(prevState => ({
  myArray: [ {"name": "object"}, ...prevState.myArray]
}))