Python中一切皆對象，在Python中的反射：通過字符串的形式操作對象的屬性

• hasattr 判斷是否有改屬性或者方法，有返回True,沒有返回false
• getattr 如果是屬性獲得該屬性的值，如果是方法獲得該方法的內存地址
• setattr
• delattr

class Person:
    role = ‘person‘
    def __init__(self,name):
        self.name = name

    def walk(self):
        print("%s is walking"%self.name)

wangys = Person(‘
 
wangys‘)

print(hasattr(wangys,‘role‘))
print(hasattr(wangys,‘name‘))
print(hasattr(wangys,‘walk‘))
print(hasattr(wangys,‘eat‘))
True
True
True
False

print(getattr(wangys,‘role‘))
print(getattr(wangys,‘name‘))
print(getattr(wangys,‘walk‘))
getattr(wangys,‘walk‘)()

person
wangys
<bound method Person.walk of <__main__
 
.Person object at 0x00000216037DDA90>>
wangys is walking

通常hasattr跟getattr結合使用

class Person:
    role = ‘person‘
    def __init__(self,name):
        self.name = name

    def walk(self):
        print("%s is walking"%self.name)

wangys = Person(‘wangys‘)

if  hasattr(wangys,‘role‘):
    print(getattr(wangys,‘
 
role‘))

if hasattr(wangys,‘walk‘):
    getattr(wangys,‘walk‘)()

if hasattr(wangys,‘eat‘):
    getattr(wangys,‘eat‘)()
else:
    print(‘沒有改方法‘)

person
wangys is walking
沒有改方法

Python面向對象之-反射