为什么两个函数调用都返回相同的值？

Question

See the code segment below:

var o = {f:function(){ return this.a + this.b; }};
var p = Object.create(o);
o.a = 10;
o.b = 20;

console.log(o.f());  // output: 30
console.log(p.f());  // output: 30

The object p doesn't have property pa and pb then how pf() return output 30. Is that prototype chain? Could anyone explain this? Thanks in advance.

Answer 1

Here o is the prototype of the p object, so all the propeties of o is available in p .

So when you call pf() , you will get the values assigned to o in this.a and this.b