使用Python覆盖属性

Question

如何覆盖Python中属性的getter？

我试图做的事：

class Vehicule(object): 

    def _getSpatials(self): 
     pass 

    def _setSpatials(self, newSpatials): 
     pass 

    spatials = property(_getSpatials, _setSpatials) 

class Car(Vehicule) 

    def _getSpatials(self): 
     spatials = super(Car, self).spatials() 
     return spatials 

但吸气呼吁VEHICULE的方法，而不是汽车。

我应该改变什么？

Answer 1

它看起来像你想要租车的空间属性的getter调用驱动车辆的 空间属性的getter。您可以通过

class Vehicule(object): 
    def __init__(self): 
     self._spatials = 1 
    def _getSpatials(self): 
     print("Calling Vehicule's spatials getter") 
     return self._spatials 
    def _setSpatials(self,value): 
     print("Calling Vehicule's spatials setter")   
     self._spatials=value 
    spatials=property(_getSpatials,_setSpatials) 

class Car(Vehicule): 
    def __init__(self): 
     super(Car,self).__init__() 
    def _getSpatials(self): 
     print("Calling Car's spatials getter") 
     return super(Car,self).spatials 
    spatials=property(_getSpatials) 

v=Vehicule() 
c=Car() 
print(c.spatials) 
# Calling Car's spatials getter 
# Calling Vehicule's spatials getter 
# 1 

另一方面，从Car的二传手中调用Vehicule的二传手更加困难。 显而易见的事情不工作：

class Car(Vehicule): 
    def __init__(self): 
     super(Car,self).__init__() 
    def _getSpatials(self): 
     print("Calling Car's spatials getter") 
     return super(Car,self).spatials 
    def _setSpatials(self,value): 
     print("Calling Car's spatials setter") 
     super(Car,self).spatials=value 
    spatials=property(_getSpatials,_setSpatials) 

v=Vehicule() 
c=Car() 
print(c.spatials) 
c.spatials = 10 
AttributeError: 'super' object has no attribute 'spatials' 

实际上，应该是调用super(Car,self)._setSpatials：

class Car(Vehicule): 
    def __init__(self): 
     super(Car,self).__init__() 
    def _getSpatials(self): 
     print("Calling Car's spatials getter") 
     return super(Car,self).spatials 
    def _setSpatials(self,value): 
     print("Calling Car's spatials setter") 
     super(Car,self)._setSpatials(value) 
    spatials=property(_getSpatials,_setSpatials) 

v=Vehicule() 
c=Car() 
print(c.spatials) 
# Calling Car's spatials getter 
# Calling Vehicule's spatials getter 
# 1 
c.spatials = 10 
# Calling Car's spatials setter 
# Calling Vehicule's spatials setter 
print(c.spatials) 
# Calling Car's spatials getter 
# Calling Vehicule's spatials getter 
# 10 

Answer 2

这可能帮助：python properties and inheritance