find index of element of array that matches to a specific value js code example

Example 1: javascript find unique values in array

// usage example:
var myArray = ['a', 1, 'a', 2, '1'];
var unique = myArray.filter((v, i, a) => a.indexOf(v) === i); 

// unique is ['a', 1, 2, '1']

Example 2: how to find the index of a value in an array in javascript

var list = ["apple","banana","orange"]

var index_of_apple = list.indexOf("apple") // 0