XXXI` Prototype ` displays prototype properties and`__ proto__` Implicit prototype properties

This belongs to js Knowledge in .

1. js Several ways to create objects in （4 Kind of ） The way ：

So let's see js Several ways to create objects in （4 Kind of ） The way ：

• adopt Object() Method to create
• Create objects literally
• Create objects through custom functions
• Create objects through factory mode

Reference resources ：https://blog.csdn.net/dearzhuoer/article/details/84574140
Let's take a look at the third way, and you'll know —— Create... Through functions ！！！
What do you mean ？ Functions are objects ？ Pretty good ！！！

2. Functions are objects ？

• stay js The object is the existence of God , Everything is the object （ Include function ）, That's how you understand .
• Every function we create , The parser will add an attribute to the function prototype（ Except for some built-in functions ）. This property is a pointer , Points to a prototype object .（ This attribute can also correspond to a prototype object ——prototype: Prototype object ）
• If this function is a normal function , Then this prototype Attributes have no effect ; But if this function is used as a constructor to create an object , Then this object will have an implicit attribute __proto__, This implied attribute __proto__ Also point to the prototype object .
  So we have the following conclusions ： Constructor name .prototype= Object name .__proto__

Reference resources ：https://blog.csdn.net/dong001687/article/details/81836575

3. prototype and __proto__

prototype： Show prototype properties
__proto__： Implicit prototype properties
As for why a display , An implicit , After reading the second point above, we also know .prototype so ,__proto__ invisible .

4. give an example ：

function Mytest(name,age){
    
    this.name = name;
    this.age = age;
}

var xiaoming = new Mytest(' Xiao Ming ',18) 
console.log(Mytest.prototype) //{constructor: ƒ}
console.log(xiaoming.__proto__) //undefined
console.log(Mytest.prototype==xiaoming.__proto__) //true