Example 1: find index of object in array javascript
a = [
{prop1:"abc",prop2:"qwe"},
{prop1:"bnmb",prop2:"yutu"},
{prop1:"zxvz",prop2:"qwrq"}];
index = a.findIndex(x => x.prop2 ==="yutu");
console.log(index);
Example 2: react array find index
//The findIndex() method returns the index of the first element
//in the array that satisfies the provided testing function.
//Otherwise, it returns -1, indicating that no element passed the test.
const array1 = [5, 12, 8, 130, 44];
const isLargeNumber = (element) => element > 13;
console.log(array1.findIndex(isLargeNumber));
// expected output: 3
Example 3: 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
Example 4: javascript findindex
const array1 = [5, 12, 8, 130, 44];
const search = element => element > 13;
console.log(array1.findIndex(search));
// expected output: 3
const array2 = [
{ id: 1, dev: false },
{ id: 2, dev: false },
{ id: 3, dev: true }
];
const search = obj => obj.dev === true;
console.log(array2.findIndex(search));
// expected output: 2
Example 5: js find index in list
let myList = ['foo', 'bar', 'qux'];
myList.indexOf('bar'); // 1
Example 6: get index of element in array js
const beasts = ['ant', 'bison', 'camel', 'duck', 'bison'];
console.log(beasts.indexOf('bison'));
// expected output: 1
// start from index 2
console.log(beasts.indexOf('bison', 2));
// expected output: 4
console.log(beasts.indexOf('giraffe'));
// expected output: -1
//*** Thanks to MDN Web Docs ***//
//https://developer.mozilla.org/fr/docs/Web/JavaScript/Reference/Objets_globaux/Array/indexOf