Python 反射

#1、判断object中有没有一个name字符串对应的方法或属性

hasattr(object,name)

#2、获取object中有没有一个name字符串对应的方法或属性
def getattr(object, name, default=None): # known special case of getattr
    """
    getattr(object, name[, default]) -> value

    Get a named attribute from an object; getattr(x, ‘y‘) is equivalent to x.y.
    When a default argument is given, it is returned when the attribute doesn‘t
    exist; without it, an exception is raised in that case.
    """
    pass
#3、设置object中有没有一个name字符串对应的方法或属性
def setattr(x, y, v): # real signature unknown; restored from __doc__
    """
    Sets the named attribute on the given object to the specified value.

    setattr(x, ‘y‘, v) is equivalent to ``x.y = v‘‘
    """
    pass
#4、删除object中有没有一个name字符串对应的方法或属性
def delattr(x, y): # real signature unknown; restored from __doc__
    """
    Deletes the named attribute from the given object.

    delattr(x, ‘y‘) is equivalent to ``del x.y‘‘
    """
    pass

class Foo:
    x=1
    def __init__(self,name):
        self.name=name

    def f1(self):
        print(‘from f1‘)


# print(Foo.x) #Foo.__dict__[‘x‘]

f=Foo(‘egon‘)

# 判断
#hasattr
print(hasattr(f,‘name‘)) #f.name
print(hasattr(f,‘f1‘)) #f.f1
print(hasattr(f,‘x‘)) #f.x

# 设置
#setattr
setattr(f,‘age‘,18)#f.age=18

# 获得
#getattr
print(getattr(f,‘name‘))#f.name
print(getattr(f,‘abc‘,None))#f.abc
print(getattr(f,‘name‘,None))#f.abc


func=getattr(f,‘f1‘)#f.f1 
print(func)
func()
#

#delattr 删除
delattr(f,‘name‘)# del f.name
print(f.__dict__)