array method indexof 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

Example 3: indexof javascript

arr.indexOf(searchElement[, fromIndex])

Example 4: js index to index

let array = [5, "Foo", 3, "Bar"];
array.slice(2);
// Output = [3, "Bar"]

let string = "Volvo Cars";
string.slice(2);
// Output = "lvo cars"