obj has own property code example
Example 1: javascript hasownproperty
var person = {
"first_name": "Bob",
"last_name": "Dylan"
};
person.hasOwnProperty('first_name'); //returns true
person.hasOwnProperty('age'); //returns false
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
}