how to get element index in javascript code example

Example 1: get the index of object in array

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: 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 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 indexof

//indexOf getting index of array element, returns -1 if not found
var colors=["red","green","blue"];
var pos=colors.indexOf("blue");//2

//indexOf getting index of sub string, returns -1 if not found
var str = "We got a poop cleanup on isle 4.";
var strPos = str.indexOf("poop");//9

Example 5: get the index of object in array

var elementPos = array.map(function(x) {return x.id; }).indexOf(idYourAreLookingFor);
var objectFound = array[elementPos];