How to convert a string of numbers to an array of numbers?

Question

I have below string -

var a = \"1,2,3,4\";

when I do -

var b = a.split(\',\');

I get b as

Answer 1

The underscore js way -

var a = "1,2,3,4",
  b = a.split(',');

//remove falsy/empty values from array after split
b = _.compact(b);
//then Convert array of string values into Integer
b = _.map(b, Number);

console.log('Log String to Int conversion @b =', b);