js check if object has value code example

Example 1: test if property exists javascript

const hero = {
  name: 'Batman'
};

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

Example 2: check if object has method javascript

if(typeof myObj.prop2 === 'function') {
    alert("It's a function");
} else if (typeof myObj.prop2 === 'undefined') {
    alert("It's undefined");
} else {
    alert("It's neither undefined nor a function. It's a " + typeof myObj.prop2);
}