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1, object-oriented
Is a programming idea is the core target
The program seen as a bunch of objects set of functions the program is to control the scheduling objects interact complete
2. Why use an object-oriented
Advantage of high scalability and flexibility, reusability,
The disadvantage is more complex program structure can not predict the results
3, classes and objects
Class is a series with the same characteristics and behavior aggregate object is an abstract concept
The object is to have a collection of things are certain characteristics and behaviors specific existence
Class contains a plurality of objects
Objects belonging to a type
4, the definition of
5, the proper use of the property
Public class objects into portions
Each object in the object's own unique namespace
Deletions attribute change search
6, initialization function
For attachment to the object and the initial value of some other initialization logic
The return value can not be returned none
7, binding method
Binding method of the object and the function object
When an object is automatically invoked incoming object itself as the first argument
When a class is an ordinary function calls that need their own traditional values
The class and binding function classes
With a class or object calls will pass the class itself
@classme
8, non-binding approach
Scene
When the logical function of access to the object bound to a subject in need then only the class data is bound to the class
Find the order to go first object properties can not find its own namespace can not find his parent looking for the class namespace classes.
Content Today
One of the three characteristics of oop
Polymorphism package inheritance
inherit
What is inherited
Inheritance is a relationship through inheritance, inherited a party can be used as one of the party has inherited some things, inherited a party called the parent, the child is called inheritance.
When the inevitable inheritance python3 create another class If not specify a parent class, the default inherited object; object is with all classes that are directly or indirectly inherited object.
Why use inheritance
1, reducing code duplication improve reusability
2, polymorphic provide the necessary support
In the program, it is the inheritance relationships between classes and class description
grammar
class 类名称（父类的名称）：
类的内容
#在python中 一个子类可以继承多个父类Abstraction and inheritance (first abstract and then inherited):
What is the abstract
The same portion of the plurality of subclasses extraction, formation of a new class of this process is also called abstraction.
Find the order
First find the object's own class resides ---- ---- ---- find parent parent parent class ---- Object
Abstract usage scenarios
Inheritance is based on the abstract result, the programming language to implement it, certainly is the first experience of this abstract process, in order to express the abstract structure by way of inheritance.
Just an abstract process analysis and design, a movement or a skill, can get through abstract class
Derivation
When a subclass occurred with different content parent class, subclass it is called a derived class
Usually sub-class will write some new code and can not be exactly like the parent that is usually derived class
So derived class refers to a subclass
cover
When the subclasses appears entirely consistent with the parent class and subclass name attribute or method
Exercise restriction element can achieve a type of container (neuron progenitor dictionary listing a collection of strings)
Subclass the parent class content access
grammar
方式一：
super（当前类名称，self）.你要调的父类的属性或方法
方式二：
super（）.你要调的父亲的属性或方法
方式三：
类名称.你要调的父类的属性或方法（self）
方式三与继承无关
Emphasize
When you inherit an existing class and you cover the parent class init method, you must call the parent class initialization method of the first line of the initialization method, passing in the required parameters parent class
combination
What kind of relationship will describe what is the relationship between the two objects
An object as a property of another object that is what what
The purpose combination
That is, to reuse existing code
When to use inheritance relationship analysis of two classes in the end is not what is the relationship between what
When used in combination if there is no significant relationship between the two classes are not completely similar
Further lower compared to the combination of inherited coupling
Diamond inheritance
First clear python support multiple inheritance
The new supplement category and Classic
python3 in any class are inherited directly or indirectly Object
The new class of any explicit or implicit Object class inherits from class to the new call in all new class python3
Classic neither a subclass of Object appears only in the python2
When there is a diamond inheritance, the new class, the first depth, when faced with a common parent class on breadth
The new class is a depth-first