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JavaScript

Tommaso Poletti
Tommaso Poletti
5,205 Points
Posted by Tommaso Poletti
Tommaso Poletti
5,205 Points

Why use .map() instead of .forEach()

In this video @Jim Hoskins for iterate the array of object in React use .map().

I know the basic differences between the two methods (.map() || .forEach() || for()).

Is a simple preference or there are a deep meaning? :)

// array of object
var PLAYERS = [
  {
    name: "polettit",
    score: 31,
  },
  {
    name: "mantovanig",
    score: 13,
  },
  {
    name: "cantellid",
    score: 33,
  },
];


// where he use map()
props.players.map(function(player) {
    return <Player name={player.name} score={player.score} />
})

Thanks in advance ;)

Tommy

1 Answer

Steven Parker
Steven Parker
231,271 Points
Steven Parker
Steven Parker
231,271 Points

Use map when you need the return values of the function.

Both map and forEach call a function for every element of the array, but only map builds a new array using the function return values.

So if you need the return values, use map; and if you don't, use forEach.