array find and findindex in javascript code example

Example 1: javascript get index of object 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 2: .findIndex(

array.findIndex(call back function)

 //index of ............
 //first