Whats the best way to update an object in an array in ReactJS?

Question

If you have an array as part of your state, and that array contains objects, whats an easy way to update the state with a change to one of those objects?

Example, mo

Answer 1

You can do this with multiple way, I am going to show you that I mostly used. When I am working with arrays in react usually I pass a custom attribute with current index value, in the example below I have passed data-index attribute, data- is html 5 convention.

Ex:

//handleChange method.
handleChange(e){
  const {name, value} = e,
        index = e.target.getAttribute('data-index'), //custom attribute value
        updatedObj = Object.assign({}, this.state.arr[i],{[name]: value});
      
  //update state value.
  this.setState({
    arr: [
      ...this.state.arr.slice(0, index),
      updatedObj,
      ...this.state.arr.slice(index + 1)
    ]
  })
  }