function Person(){
}
// 对象的原型 keys
Person.prototype.name = "Nicholas";
Person.prototype.age = 29;
Person.prototype.job = "Software Engineer";
Person.prototype.sayName = function(){
console.log(this.name);
};
// keys
var keys = Object.keys(Person.prototype);
console.log(keys); //"name,age,job,sayName"
// names
var names = Object.getOwnPropertyNames(Person.prototype);
console.log(names); //"constructor,name,age,job,sayName"