javascript loop through object array

var person={
 	first_name:"johnny",
  	last_name: "johnson",
	phone:"703-3424-1111"
};
for (var property in person) {
  	console.log(property,":",person[property]);
}for (var prop in obj) {
    if (Object.prototype.hasOwnProperty.call(obj, prop)) {
        // do stuff
    }
}