python反射的简单应用

class Cartoon(object):

    def __init__(self):
        self.name = "哪吒"

    def func(self):
        return "魔童降世"


# 创建要操作的类的对象
obj = Cartoon()

# 1. 查看属性
print(obj.name)

# 2. 判断类中是否有该成员,当找到第二个参数时返回true，否则返回false
have_1 = hasattr(obj, "func")
have_2 = hasattr(obj, "drink")
print(have_1)
print(have_2)

# 3. 获取对象的值.
res_name = getattr(obj, "name")  # 返回属实际性值. 如果没有此属性,程序报异常
# res_wrong1 = getattr(obj,"job")  # 如果获取没有的属性或方法,会报错: AttributeError: 'Cartoon' object has no attribute 'job'
res_method = getattr(obj, "func")  # 返回方法的内存地址
r = res_method()  # 执行方法
print(res_method)
print(res_name)
print(r)

# 4. 设置属性值
res = setattr(obj, "name", "三太子")
print(obj.name)

# 5. 添加属性和值. 当设置的属性不存在时，会自动添加到属性和对应值到对象中
setattr(obj, "age", "3")  # 相当于 obj.age = 3
print("name={0},age={1}".format(obj.name, obj.age))

# 6. 删除对象的属性
delattr(obj, "age")

print(dir(obj))  # 查看大部分属性和方法.
# ['__class__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__',
# '__gt__', '__hash__', '__init__', '__init_subclass__', '__le__', '__lt__', '__module__', '__ne__', '__new__',
# '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__',
# 'func', 'name']  #最后展示的是方法名和属性名