loop failing to refresh element within array

Is there a way to update a specific property in every element of an array to match its index? I attempted the following approach:

  static reindexComponentsOnMultiplePages(components) {
    return components.forEach((el, idx) => (el.componentIndex = idx));
  }

However, this returned undefined. Here is how my current array looks like:

components = [ 
               [ {...}, {...}, {...} ], 
               [ {...}, {...}, {...} ] 
             ]

I expected each property in every element of the array to be updated accordingly. The method was called like so:

pageComponents = MyService.reindexComponentsOnMultiplePages(pageComponents);

Answer №1

Array.forEach() does not return any value according to the information provided in the official documentation.

When using the forEach method, there is no need to explicitly return the array since the items are being updated within the loop.

var arr = [{name: 'A', componentIndex: null}, {name: 'B', componentIndex: null}];
console.log(arr);

arr.forEach(function(item, index) {
  item.componentIndex = index;
});

console.log(arr);

It is advised to avoid returning anything during a forEach iteration as it is unnecessary in this context.

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