How to get index (offset) of the array of objects when value of a property of its element object is known?

Here is the solution

First create a new array of the elements of the know property only, using the function. And then chain it with indexOf(knownValue). This will actually give u the index of the value in current new array but is the required index of the element object you are looking for.

var array = [{ name: 'abc', 
  property: 'something',
  anotherproperty: 'somethingelse'

var index = {