There is a special method Array.isArray
that can be used to check whether a variable
contains a real array or not. Let's test the
method.
An array:
let test = [1, 2, 3];
let res = Array.isArray(test);
console.log(res); // shows true
An object:
let test = {a: 1, b: 2, c: 3};
let res = Array.isArray(test);
console.log(res); // shows false
A primitive:
let test = 'abcde';
let res = Array.isArray(test);
console.log(res); // shows false
A pseudo-array:
let test = document.querySelectorAll('p');
let res = Array.isArray(test);
console.log(res); // shows false
Given a two-dimensional array:
let test = [
[1, 2, 3],
{a: 1, b: 2, c: 3},
[3, 4, 5],
{x: 1, y: 2, z: 3},
];
Loop through this array and for each element check if it is an array or not.