obj.prototype = shuxing；
shuxing['属性']=值；
function Person(){};
var person = new Person();
person.name = 'yy';
person.gender = 'girl';
console.log(person.name+','+person.gender);//yy,girl
delete person.name;//删除属性
console.log(person.name);//undefined
// 变式
function Person(){};
var person = new Person();
person['name'] = 'yy';
person['gender'] = 'girl';
console.log(person.name+','+person.gender);//yy,girl
delete person.name;//删除属性
console.log(person.name);//undefined