object has property js code example
Example 1: js check if object has property
const object1 = new Object();
object1.property1 = 42;
console.log(object1.hasOwnProperty('property1'));
// expected output: true
Example 2: javascript does object have property
var person = {'first_name': 'bill','age':20};
if ( person.hasOwnProperty('first_name') ) {
//person has a first_name property
}
Example 3: how reliable is js hasownproperty
o = new Object();
o.propOne = null;
o.hasOwnProperty('propOne'); // returns true
o.propTwo = undefined;
o.hasOwnProperty('propTwo'); // returns true