JavaScript | Arrays | .forEach()

.forEach()

The .forEach() array method loops over the array, passing each item in the array into the callback function provided.

Syntax

array.forEach((value, index, array) => {...});

A function can be invoked with three arguments:

value: The value of the array element.
index (optional): The index of the array element.
array (optional): The array itself.

Note: Unlike a regular for loop, .forEach() method does not provide a way to terminate iteration before all elements have been passed to the function.

Example 1

Logging each value in an array:

['a', 'b', 'c'].forEach((letter) => console.log(letter));

The output would be:

a
b
c

Example 2

Finding the sum of an array:

const values = [7, 17, 34, 41, 22, 5];
let sumOfValues = 0;

values.forEach((value) => (sumOfValues += value));

console.log(sumOfValues);
// Output: 126