Python class attribute and instance attribute usage analysis

This article analyzes the Python class attribute and instance attribute usage. Share to everyone for your reference. Specifically as follows:

Class attribute: Class name. property name

Instance properties: Instance. Property name

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>>> class Test (): ... ver=1 >>> a=test () >>> test.x=8 >>> a.__dict__ {} >>&G T a.x 8 >>> a.x=9 >>> a.__dict__ {' x ': 9}

1. The properties of the class are the same, and once the class attribute is given, all instances will take this value.

2. The value of this property of each instance can vary.

3. The attribute of an instance is not given as shown, a.x can display the value of the property, but it is not in the namespace.

In order to add it to the namespace, you must explicitly assign the value.

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Class Instant1 (object): Count=0 def __init__ (self): instant1.count=instant1.count+1 print "created instant" Def howmany ( Self): print Instant1.count Print Self.count class Instant2 (object): Count=0 def __init__ (self): print Self.count #print Instant2.count self.count=self.count+1 #Instant2. count=instant2.count+1 print "created instant" Def Howmany (self): Print Self.count Print Instant2.count

I hope this article will help you with your Python programming.