javascript array indexof + function code example
Example 1: javasript array indexof
var array = [2, 9, 9];
array.indexOf(2); // 0
array.indexOf(7); // -1
array.indexOf(9, 2); // 2
array.indexOf(2, -1); // -1
array.indexOf(2, -3); // 0
Example 2: JavaScript Array Methods indexOf()
let days = ['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday'];
console.log(days.indexOf('Sunday'));
// --> -1, mert nem található meg
let days = ['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday'];
console.log(days.indexOf('Monday'));
// --> 0