array find index javascript code example

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: javascript get index of object with value in array

// Get index of object with specific value in array
const needle = 3;
const haystack = [{ id: 1 }, { id: 2 }, { id: 3 }];
const index = haystack.findIndex(item => item.id === needle);

Example 4: 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 5: 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 6: js find index in list

let myList = ['foo', 'bar', 'qux'];

myList.indexOf('bar');	// 1