js prototype 和 hasOwnProperty的几个例子

var obj = {id: 3};
obj.prototype.set = function(){ // 报错，因为obj是‘普通对象’
this.name = 'wy';
};
alert(obj.hasOwnProperty('id'));

var obj = {id: 3};
obj.prototype.name = 'yw'; // 报错，因为obj是‘普通’

var Obj = function(){
this.id = 3;
};
alert(Obj.hasOwnProperty('id')); // false,因为Obj是"函数对象"，不是"普通对象"

var Obj = function(){
this.id = 3;
};
Obj.prototype.set = function(){
this.name = 'wy';
};
var o = new Obj();
alert(o.hasOwnProperty('id')); // true
alert(o.hasOwnProperty('name')); // false

var Obj = function(){
this.id = 3;
};
Obj.prototype.set = function(){
this.name = 'wy';
};
var o = new Obj();
o.set(); // 注意
alert(o.hasOwnProperty('id')); // true
alert(o.hasOwnProperty('name')); // 注意：true

var Obj = function(){
this.id = 3;
};
Obj.prototype.name = 'wy';
var o = new Obj();
alert(o.hasOwnProperty('name')); // false

var Obj = function(){
this.id = 3;
};
Obj.prototype.name = 'wy';
Obj.prototype.set = function(){
Obj.prototype.name = 'hello'; // 赋值
};
var o = new Obj();
o.set();
alert(o.hasOwnProperty('name')); // false

var Obj = function(){
this.id = 3;
};
var o = new obj();
o.name = 'wy';
alert(o.hasOwnProperty('name')); // true,直接给对象赋值

var Obj = function(){
this.id = 3;
};
Obj.prototype.name = 'wy';
var o = new Obj();
alert(Obj.prototype.hasOwnProperty('name')); // true,直接访问原型链

var Obj = function(){
this.id = 3;
};
Obj.prototype.set = function(na){
this.name = na;
};
var o1 = new Obj();
o1.set('wy');
var o2 = new Obj();
o2.set('lh');
alert(o1.name); // wy
alert(o2.name); // lh