Is It Possible To Get The Non Enumerable Inherited Property Names Of An Object

When working with objects in JavaScript, you may come across a situation where you need to access inherited property names that are non-enumerable. This can be a bit tricky, but fear not, because there is a way to achieve this! In this article, we will explore how you can get the non-enumerable inherited property names of an object.

First things first, let's understand what enumerable and non-enumerable properties are. In JavaScript, enumerable properties are those that can be iterated over using a for...in loop, while non-enumerable properties are not shown when iterating over an object's properties. Objects can have both their own properties and properties inherited from their prototype chain.

To tackle the task of retrieving non-enumerable inherited property names of an object, we can make use of the `Object.getOwnPropertyNames()` method along with a recursive function. The `Object.getOwnPropertyNames()` method returns an array of all properties (enumerable or not) found directly upon a given object.

We can create a function that utilizes `Object.getOwnPropertyNames()` to get the non-enumerable properties at each level of the prototype chain. Here's an example of how you can achieve this:

function getNonEnumerableInheritedPropertyNames(obj) {
  let result = [];
  
  let proto = obj;

  while (proto) {
    const nonEnumProps = Object.getOwnPropertyNames(proto)
      .filter(prop => !Object.getOwnPropertyDescriptor(proto, prop).enumerable);

    result = result.concat(nonEnumProps);

    proto = Object.getPrototypeOf(proto);
  }

  return result;
}

// Example usage
const sampleObj = {};
const nonEnumProps = getNonEnumerableInheritedPropertyNames(sampleObj);
console.log(nonEnumProps);

In the code snippet above, the `getNonEnumerableInheritedPropertyNames()` function accepts an object `obj` and returns an array containing the non-enumerable inherited property names of that object.

The function starts by initializing an empty array `result` to store the non-enumerable properties. It then iterates over each level of the object's prototype chain using a while loop. For each level, it uses `Object.getOwnPropertyNames()` to retrieve all property names, then filters out only the non-enumerable ones using `Object.getOwnPropertyDescriptor()`.

By concatenating these non-enumerable properties at each level, we build up a final array that contains all the non-enumerable inherited property names of the object.

So, there you have it! With the help of the `Object.getOwnPropertyNames()` method and a recursive function, you can now confidently access the non-enumerable inherited property names of an object in JavaScript. Happy coding!