Object has-property-deep check in JavaScript

Question

Let\'s say we have this JavaScript object:

var object = {
   innerObject:{
       deepObject:{
           value:\'Here am I\'
       }
   }
};

<

Answer 1

I have created a very simple function for this using the recursive and happy flow coding strategy. It is also nice to add it to the Object.prototype (with enumerate:false!!) in order to have it available for all objects.

function objectHasOwnNestedProperty(obj, keys)
{
  if (!obj || typeof obj !== 'object')
  {
    return false;
  }

  if(typeof keys === 'string')
  {
    keys = keys.split('.');
  }

  if(!Array.isArray(keys))
  {
    return false;
  }

  if(keys.length == 0)
  {
    return Object.keys(obj).length > 0;
  }

  var first_key = keys.shift();

  if(!obj.hasOwnProperty(first_key))
  {
    return false;
  }

  if(keys.length == 0)
  {
    return true;
  }

  return objectHasOwnNestedProperty(obj[first_key],keys);
}

---

Object.defineProperty(Object.prototype, 'hasOwnNestedProperty',
{
    value: function () { return objectHasOwnNestedProperty(this, ...arguments); },
    enumerable: false
});