Object-oriented review

By object-oriented function package to give a class,

Nature or function of a class: Remarks

1 for each class ( function ) born with a prototype attributes, the prototype is an object, the object which has a Construction ( Constructor ) attribute, the attribute value is the class itself.

2 All of our new class, when, in fact, is calling its constructor. Constructor is private property, constructor of this is an instance of an object.

3 born with one on each object the __proto__ , point to the class prototype.

 

function Person(){
  
 }
 var zhangsan=new Person;
 console.dir(zhangsan)
 console.log(zhangsan.__proto__==Person.prototype)

Prototype __proto__

  1. prototype is a class or function, the __proto__ is subject
  2. Prototype is a storage mechanism, __proto__ is to find mechanisms

Zhangsan.name

Zhangsan this object first look at the name is private, is used directly, instead of on the adoption of __proto__ go on its class prototype look, there is the direct use, not to keep looking up, until you find the base class Object , not that undefined , there is the direct use. This discovery mechanism called the prototype chain.

Special Function

1 class

2 function

3 objects

4. Each function is born with a return value, return of what it is, if no return is undefined

 

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Origin www.cnblogs.com/yuanyeds/p/11313420.html