check if all the property exists javascript code example

Example 1: how to check wether the property exist in a object in java script

if (obj.hasOwnProperty('prop')) {
    // do something
}

Example 2: test if property exists javascript

const hero = {
  name: 'Batman'
};

hero.hasOwnProperty('name');     // => true
hero.hasOwnProperty('realName'); // => false