js how to return copy of array code example

Example 1: javascript copy array

// this is for array with complex object
var countries = [
  {name: 'USA', population: '300M'}, 
  {name: 'China', population: '1.6B'}
];

var newCountries = JSON.parse(JSON.stringify(countries));

Example 2: javascript copy array

var oldColors=["red","green","blue"];
var newColors = oldColors.slice(); //make a clone/copy of oldColors