Question

我定义了我的类变量“ count_instance”，以便计算用我的类“ Person”创建的实例数。初始化之后，我编写了命令“ Person.count_instance + = 1”。这样一来，每创建一个新实例，我的count_instance就会增加1。

但是，当我创建类的实例（对象）时，会导致错误提示：“ + =：'method'和'int'的操作数类型不受支持”。

有人可以帮助我为什么会这样吗？以及如何解决此问题。我正在使用python 3.6

我试图检查语义和句法错误。但是我无法解决这个问题。

    class Person:
        count_instance = 0
        def __init__(self, first_name, last_name, age): # These are attributes in the bracket and init is the initialization method.
    #Instance Variable declaration
            Person.count_instance +=1
            self.first_name = first_name
            self.Last_name = last_name
            self.age = age
        @classmethod
        def count_instance(cls):
            return f"You have created {cls.count_instance} of Person Class"

        def full_name(self):
            return(f"{self.first_name} {self.last_name}")

        def is_above_18(self):
            return self.age>18

    #Creating the instances
    p1 = Person("Sara", "Kat", 18)
    p2 = Person("Pankaj", "Mishra", 26)

enter image description here TypeError：+ =：“方法”和“ int”的不受支持的操作数类型

Answer 1

count_instance在代码中既是变量又是方法。两者都使用唯一的名称。例如，将方法更改为print_count_instance：

class Person:
    count_instance = 0
    def __init__(self, first_name, last_name, age): # These are attributes in the bracket and init is the initialization method.
#Instance Variable declaration
        Person.count_instance +=1
        self.first_name = first_name
        self.Last_name = last_name
        self.age = age
    @classmethod
    def print_count_instance(cls):
        return f"You have created {cls.count_instance} of Person Class"

    def full_name(self):
        return(f"{self.first_name} {self.last_name}")

    def is_above_18(self):
        return self.age>18

#Creating the instances
p1 = Person("Sara", "Kat", 18)
p2 = Person("Pankaj", "Mishra", 26)

p1.print_count_instance()

使用类变量和类方法计数实例创建时，不受支持的操作数类型错误

1 个答案: