Python的元编程和反射使用案例

[python]代码库

class MyClass:
    my_attribute = 42

    def my_method(self, arg):
        print(f"This is my_method with arg {arg}.")

obj = MyClass()

print(hasattr(obj, "my_method"))
print(hasattr(obj, "my_attribute"))

# Output:
# True
# True

# Using getattr to access an attribute
print(getattr(obj, "my_attribute"))

# Output:
# 42

# Using setattr to add an attribute
setattr(obj, "new_attribute", "hello")
print(obj.new_attribute)

# Output:
# hello

# Using delattr to delete an attribute
delattr(obj, "new_attribute")
print(hasattr(obj, "new_attribute"))

# Output:
# False

# Dynamically creating a class
MyDynamicClass = type("MyDynamicClass", (), {"my_attribute": 42, "my_method": lambda self, arg: print(f"This is my_method with arg {arg}.")})

obj2 = MyDynamicClass()

print(obj2.my_attribute)
obj2.my_method("test")

# Output:
# 42
# This is my_method with arg test.