关于对象+原型+继承（一）

 1 var a={
 2       x:2,
 3       getNumber:function(z){
 4          return this.x+this.y+z;
 5       }                          
 6 } ;   
 7 
 8 
 9 var b={
10       y:23,
11      __proto__:a;  
12 //表示对象b继承至对象a;__proto__属性为为对象自身隐含属性     
13 } ;  
14 
15 b.getNumber(4);//输出29

 1 var a={ x:1,cal:function(z){return this.x+this.y+z;}};var b={y:3};  b=Object.create(a);b.y;
 2 //undefined b对象中的属性y被覆盖
 3 
 4 var a={ x:1,cal:function(z){return this.x+this.y+z;}};var b={y:3};  b=Object.create(a);b.x;
 5 //1
 6 
 7 var a={ x:1,cal:function(z){return this.x+this.y+z;}};var b={y:3};  b=Object.create(a);b.cal;
 8 // function a.cal(z)，输出a对象的属性
 9 
10 var a={ x:1,cal:function(z){return this.x+this.y+z;}};var b={y:3};  b=Object.create(a);b;
11 //Object {}
12 
13 var a={ x:1,cal:function(z){return this.x+this.y+z;}};var b={y:3};  b=Object.create(a);b.cal(23);
14 //NaN，此时b对象中的属性y被覆盖
15 
16 
17 var a={ x:1,cal:function(z){return this.x+this.y+z;}};var b=Object.create(a);b.y=2;b.cal(23);
18 //26  手动添加对象b的属性y