How to edit an item in a state array?

Question

So here is my state:

this.state = {
  ids: [\'A\', \'E\', \'C\']
};

How would I go about modifying the state so that \'E\' at index 1 is change

Answer 1

Case 1: If you know the index then you can write it like this:

let ids = [...this.state.ids];     // create the copy of state array
ids[index] = 'k';                  //new value
this.setState({ ids });            //update the value

Case 2: If you don't know the index then first use array.findIndex or any other loop to get the index of item you want to update, after that update the value and use setState.

Like this:

let ids = [...this.state.ids];  
let index = ids.findIndex(el => /* condition */);
ids[index] = 'k';                  
this.setState({ ids });