var person = {
"first_name": "Bob",
"last_name": "Dylan"
};
person.hasOwnProperty('first_name'); //returns true
person.hasOwnProperty('age'); //returns falseconst object1 = new Object();
object1.property1 = 42;
console.log(object1.hasOwnProperty('property1'));
// expected output: truevar person = {'first_name': 'bill','age':20};
if ( person.hasOwnProperty('first_name') ) {
//person has a first_name property
}
o = new Object();
o.propOne = null;
o.hasOwnProperty('propOne'); // returns true
o.propTwo = undefined;
o.hasOwnProperty('propTwo'); // returns true
hero.hasOwnProperty('name'); // => true