classmethod与staticmethod内置装饰器

class DB:
    __data = "tom is very cute"
    def __init__(self, user, pwd, role):
        self.user = user
        self.pwd = pwd
        self.role = role

    @classmethod
    def check_db(cls, user, pwd, role):    # cls指的是类
        # 在类方法内部调用类产生一个实例  --->  对象
        obj = cls(user, pwd, role)
        # 查看数据前必须通过校验
        if obj.user == "root" and obj.pwd == "123" and obj.role == "admin":
            return cls.__data

print(DB.check_db("root", "123", "admin"))

tom is very cute

class Foo:
    @staticmethod
    def func(self):
        print(self)

obj = Foo()
# 对象调用非绑定方法
obj.func(123)

# 类调用非绑定方法
Foo.func(1234)

123
1234