为什么我不断收到此属性错误？

Question

每次我运行我的代码时，它都会弹出消息说“‘ICU’ object 没有属性‘_name’。你是说：‘name’吗？” 我不知道如何解决它。 我已经尝试更改访问器和修改器的名称，但仍然无法弄清楚如何解决它。 有什么建议么？

这是我的代码：

class Patient:
    def __init__(self, name, age):
        self.name = name
        self.age = age
        self.weight = 150

    @property
    def age(self):
        return self._age

    @age.setter
    def age(self, newValue):
        if newValue > 0:
            self._age = newValue
        else:
            self._age = 0

    @property
    def weight(self):
        return self._weight


    @weight.setter
    def weight(self, newValue):
        if newValue >=0 and newValue <= 1400:
            self._weight = newValue


    #IncreaseAge
    def increaseAge(self):
        self.age = self.age + 1

class In(Patient):
    def __init__(self, name, age, stay):
        self.name = name
        self.age = age
        self.stay = stay

    @property  
    def stay(self):
        return self._stay

    @stay.setter
    def stay(self, value):
        self._name = value

    def __str__(self):
        print("IN-" + self._name + self._age + self.weight + self._stay)

class Out(Patient):
    def __init__(self, name, age):
        self.name = name
        self.age = age

    def __str__(self):
        print("OUT-" + self._name + self._age + self._weight)

class ICU(In):
    def __init__(self, name, age):
        self.name = name
        self.age = age
        self.days = 5 

class CheckUp(Out):
    def __init__(self, name, age):
        self.name = name
        self.age = age 

这是实例的 rest：

# Create three patient objects and print them out
p1 = ICU("Ben Dover", 0)
p2 = ICU("Helen Hywater", -15)
p3 = CheckUp("Amanda Lynn", 45)
p4 = ICU("Chester Minit", 12)
p5 = In("Don Keigh", 89, 10)
p6 = Out("Kay Oss ", 45)
print ("\tStatus\tName\t\tAge\tWeight\tStay")
print ("-" * 55)
print ("p1:\t{}".format(p1))
print ("p2:\t{}".format(p2))
print ("p3:\t{}".format(p3))
print ("p4:\t{}".format(p4))
print ("p5:\t{}".format(p5))
print ("p6:\t{}".format(p6))

print ("-" * 55)

# Change their ages and print them out
p1.age = -5
p2.age = 100
for i in range(6):
    p3.increaseAge()
p4.age = 0
p5.increaseAge()
p6.age = 42

print ("p1:\t{}".format(p1))
print ("p2:\t{}".format(p2))
print ("p3:\t{}".format(p3))
print ("p4:\t{}".format(p4))
print ("p5:\t{}".format(p5))
print ("p6:\t{}".format(p6))
print ("-" * 55)

# Change other instance variables and print them out
p1.weight = 2000
p1.stay = 3
p2.name = "Justin Thyme"
p2.weight = 220
p2.stay = 0
p3.weight = -50
p4.weight = 1400
p5.weight = 0
p5.stay = 21
p6.weight = 1401

print ("p1:\t{}".format(p1))
print ("p2:\t{}".format(p2))
print ("p3:\t{}".format(p3))
print ("p4:\t{}".format(p4))
print ("p5:\t{}".format(p5))
print ("p6:\t{}".format(p6))
print ("-" * 55)

Answer 1

这是因为你的变量名不同。 替换您的代码：

@stay.setter
def stay(self, value):
    self._name = value

到：

@stay.setter
def stay(self, value):
    self.name = value

Answer 2

在 Python 中，构造函数 - 与所有其他方法一样 - 可以被覆盖。 也就是说，一旦您在子类中定义了__init__ ，就永远不会调用基 class 方法。 这就是导致错误的原因。 您需要像这样显式调用基数 class：

class ICU(In):
    def __init__(self, name, age):
        self.name = name
        self.age = age
        self.days = 5 
        In.__init__(self, name, age, 10) # stay = 10 since it's not an input parameter in the ICU __init__ method.

这需要在每个 base class 中完成。所以你也会在In class 中做类似的事情。

Answer 3

问题在于“格式”正在您的实例上调用“__ str__”，但是当调用“__ str__”时，您的某些实例没有“_name”或“_stay”或“_weight”的值...查看每个实例的“__init__”方法，并在看到问题后执行“__str__”。 所以要处理这种情况，您有以下简单的解决方案

 class In(Patient):
    def __init__(self, name, age, stay):
        self.name = name
        self.age = age
        self.stay = stay

    @property  
    def stay(self):
        return self._stay

    @stay.setter
    def stay(self, value):
        self._name = value

    def __str__(self):
        x = (
            getattr(self, '_name', ''),
            getattr(self, '_age', ''),
            self.weight or ''
            getattr(self, '_stay', ''),
        )
        return ("IN-%s %s %s %s")%(*x)


class Out(Patient):
    def __init__(self, name, age):
        self.name = name
        self.age = age

    def __str__(self):
        x = (
            getattr(self, '_name', ''),
            getattr(self, '_age', ''),
            getattr(self, '_stay', ''),
        )
        return "OUT- %s %s %s"%(*x)

但是你的课程设计得不好，请看下面的一些有趣的东西

class Patient:
    def __init__(self, name, age,  weight=150):
        self._name= name
        self._age = age
        self._weight = weight

    @property
    def name(self):
        return self._name

    @name.setter
    def name(self, value):
        assert isinstance(value, str)
        self._name = value

    @property
    def age(self):
        return self._age

    @age.setter
    def age(self, value):
        assert isinstance(value, int)
        self._age = value

    @property
    def weight(self):
        return self._weight

    @weight.setter
    def weight(self, value):
        assert isinstance(value, int)
        self._weight = value

    def __str__(self):
        return f"{self.__class__.__name__.upper()}-{self.name} {self.age} {self.weight}"


class Out(Patient):
    pass

class In(Patient):
    def __init__(self, name, age, stay, weight=150):
        super().__init__(name, age, weight=weight)
        self._stay = stay

    @property
    def stay(self):
        return self._stay

    @stay.setter
    def stay(self, value):
        assert isinstance(value, int)
        self._stay = value

    def __str__(self):
        return f"{super().__str__()} {self.stay}"

class ICU(In):
    def __init__(self, name, age):
        super().__init__(name, age, 5)

class CheckUp(Out):
    def __init__(self, name, age):
        super().__init__(name, age)

另请注意，您的实例未定义“increaseAge”方法