JavaScript: Retrieve a set of properties indicated by the given selectors from an object

JavaScript fundamental (ES6 Syntax): Exercise-49 with Solution

Write a JavaScript program to retrieve a set of properties indicated by the given selectors from an object.

• Use Array.prototype.map() for each selector, String.prototype.replace() to replace square brackets with dots.
• Use String.prototype.split('.') to split each selector.
• Use Array.prototype.filter() to remove empty values and Array.prototype.reduce() to get the value indicated by each selector.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2 
const get = (from, ...selectors) =>
  [...selectors].map(s =>
    s
      .replace(/\[([^\[\]]*)\]/g, '.$1.')
      .split('.')
      .filter(t => t !== '')
      .reduce((prev, cur) => prev && prev[cur], from)
  );
const obj = { selector: { to: { val: 'val to select' } }, target: [1, 2, { a: 'test' }] };

console.log(get(obj, 'selector.to.val', 'target[0]', 'target[2].a')); 

Sample Output:

["val to select",1,"test"]

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-1-49 by w3resource (@w3resource) on CodePen.

Improve this sample solution and post your code through Disqus

Previous: Write a JavaScript program to get an array of function property names from own (and optionally inherited) enumerable properties of an object.
Next: Write a JavaScript program to convert an integer to a suffixed string, adding am or pm based on its value.