js if item in arrray code example

Example 1: js array includes

[1, 2, 3].includes(2);     // true
[1, 2, 3].includes(4);     // false
[1, 2, 3].includes(3, 3);  // false
[1, 2, 3].includes(3, -1); // true
[1, 2, NaN].includes(NaN); // true

Example 2: see if array contains array javascript

const found = arr1.some(r=> arr2.indexOf(r) >= 0)