JS's prototype

Prototype and prototypes are two different things, and he's just a preset attribute on Foo. A prototype is a property on an object that points to Foo. Then we can make the shared variable or method by the method of the prototype assignment, like the X assignment on the top.

Method parsing:
1,object.create ()

method creates an empty object that has the specified prototype and several specified properties;

such as Student.prototype=object.create (Persion.prototype );

do not let student instances of __PROTO__ also have those unnecessary methods

student can define the same method as Persion, which is equivalent to rewriting the method in Persion

Instance:

Analytic diagram

Prototype the effect of the modification of the property value on the object before and after creation

1. Effect of property value modification on a created object

2. For objects created later

determines whether the property is again modified in the object

JS's prototype