Class characteristics of Pyton

The Python class resembles a container and is a dynamic container that can add content to it at any time: its functions, its members.

For example, the default is to create an empty Python class, and if you forget to add a member function to it, you can do so.

Class Empty:

Pass

1. Add constructors

#这里必须要传入一个参数

#该参数也就是调用方的输入数据

#这里就是Empty的一个实例对象

def Empty_con (E):

The print ' empty object starts to construct '

Print (Type (e))

empty.__init__ = Empty_con

Here we test:

e1 = Empty ()

The results of the discovery are as follows:

The empty object starts to construct the

<type ' instance ' >

2. For the same reason, we can add (or replace) his destructor

def empty_des (E):

The print ' object starts to deconstruct '

Print (Type (e))

empty.__del__ = Empty_des

Here we also test the destructor:

E2 = Empty ()

del E2

The output is as follows:

' The object begins to deconstruct

<type ' instance ' >

3. We can also add a member variable to a class (type) by analogy.

When you can also add members to objects only

empty.x = 100

EMPTY.Y = 200

by calling dir (empty) you can clearly see the member structure below empty.

Class characteristics of Pyton