9.1.1, private variable, private method, 9.1.1 private variable method

9.1.1, private variable, private method, 9.1.1 private variable method
Private variable, private method:

• Python is privatized to plan private attributes and avoid unrelated access! I have a wife. You cannot know who my wife is. You only need to ask me, that is, my private attributes are only known to me]
• To define private variables and private methods in python, you only need to add the underscore "_" before the variable name or function name.
• Self. _ variable name or function name used in internal methods of the class.
• In fact, if you really want to access private variables and private methods, you can also access them, because the private operation actually only changes the variable or function name:
  • In the following example, the value of private_value is changed to _ A _ private_value [that is, _ class name__ attribute name]. However, we do not recommend that you use this method for private access.

  Class A: _ private = 6 _ private_value = 5 def _ private_func (self): print ("hello") def get_private_value (self): return self. _ private_valuea = A () # print (. _ private_value) ### error. The print (. get_private_value () print (. _ A _ private_value)

• Inheritance of private variables and Methods: [subclass does not inherit the private attributes of the base class, but it is still obtained through the function of the base class or can be forcibly accessed]

Class A: _ private = 6 _ private_value = 5 def _ private_func (self): print ("hello") def get_private_value (self): return self. _ private_valueclass B (A): passb = B () # print (B. _ private_value) # print (B. get_private_value () # You can use the parent class method to obtain the private property print (B. _ A _ private_value) # mandatory access is acceptable.