concat Examples

The general syntax for this method is:

arrayName.concat(otherArray1, otherArray2, ...)

This method adds the elements of one array to the end of another. The new array must be stored in a variable or printed to the screen, because concat does NOT alter the original arrays.

Example

let arr = [1, 2, 3];
let otherArray = ['M', 'F', 'E'];
let newArray = [];

newArray = arr.concat(otherArray);
console.log(newArray);

newArray = otherArray.concat(arr);
console.log(newArray);

console.log(arr.concat(otherArray, arr));

console.log(arr);

Output

[1, 2, 3, 'M', 'F', 'E']
[ 'M', 'F', 'E', 1, 2, 3 ]
[ 1, 2, 3, 'M', 'F', 'E', 1, 2, 3 ]
[1, 2, 3]