Python中属性和属性之间的区别

类属性：类属性对于每个类都是唯一的。类的每个实例都将具有此属性。

例子：

Python3

# declare a class
class Employee: 
    
    # class attribute
    count = 0      
        
    # define a method
    def increase(self): 
        Employee.count += 1
    
# create an Employee 
# class object
a1 = Employee() 
  
# calling object's method
a1.increase() 
  
# print value of class attribute
print(a1.count) 
     
a2 = Employee() 
  
a2.increase() 
  
print(a2.count) 
    
print(Employee.count)

输出：

1
2
2

在上面的例子中，count 变量是一个类属性。

实例属性：实例属性对于每个实例都是唯一的（实例是对象的另一个名称）。每个对象/实例都有自己的属性，可以在不影响其他实例的情况下进行更改。

例子：

Python3

# create a class
class Employee: 
    
    # constructor
    def __init__(self): 
        
        # instance attribute
        self.name = 'Gfg'
        self.salary = 4000
    
    # define a method
    def show(self): 
        print(self.name) 
        print(self.salary) 
  
# create an object of 
# Employee class
x = Employee()
  
# method calling
x.show()

输出：

Gfg
4000

现在，让我们看一个关于属性的示例：

1) 使用property()函数创建类的属性：

Syntax: property(fget, fset, fdel, doc)

例子：

Python3

# create a class
class gfg: 
    
    # constructor
    def __init__(self, value): 
        self._value = value 
            
    # getting the values 
    def getter(self): 
        print('Getting value') 
        return self._value 
            
    # setting the values 
    def setter(self, value): 
        print('Setting value to ' + value) 
        self._value = value 
            
    # deleting the values 
    def deleter(self): 
        print('Deleting value') 
        del self._value 
      
    # create a properties
    value = property(getter, setter, deleter, ) 
    
# create a gfg class object
x = gfg('Happy Coding!') 
print(x.value) 
    
x.value = 'Hey Coder!'
    
# deleting the value
del x.value

输出：

Getting value
Happy Coding!
Setting value to Hey Coder!
Deleting value

2) 使用@property装饰器创建类的属性：

我们可以使用@property 装饰器来应用属性函数。这是内置装饰器之一。装饰器只是一个函数，它接受另一个函数作为参数并通过包装它来添加它的行为。

例子：

Python3

# create a class
class byDeco: 
    
   # constructor
    def __init__(self, value): 
        self._value = value 
            
    # getting the values
    @property              
    def value(self): 
        print('Getting value') 
        return self._value 
            
    # setting the values     
    @value.setter 
    def value(self, value): 
        print('Setting value to ' + value) 
        self._value = value 
            
    # deleting the values 
    @value.deleter 
    def value(self): 
        print('Deleting value') 
        del self._value 
    
    
# create an object of class
x = byDeco('happy Coding') 
print(x.value) 
    
x.value = 'Hey Coder!'
    
# deleting the value
del x.value

输出：

Getting value
happy Coding
Setting value to Hey Coder!
Deleting value

Attribute V/s Property之间的区别表

Attribute	Property
Attributes are described by data variables for example like name, age, height etc.	Properties are special kind of attributes.
Two types of attributes: Class attribute Instance attribute	It has getter, setter and delete methods like __get__, __set__ and __delete__ methods.
Class attributes are defined in the class body parts usually at the top.	We can define getters, setters, and delete methods with the property() function.
Instance attribute are defined in the class body using self keyword usually it the __init__() method.	If we just want to the read property, there is also a @property decorator which you can add above your method.