python中的setattr的使用

在python中经常会遇到给类的__init__方法中创建属性。

当要创建的属性是任意给定的时就需要用到setattr这个函数。

class Person(object):
    def __init__(slef,name,gender,birth):
        slef.name = name
        slef.gender = gender
        slef.birth = birth

xiaoming = Person('Xiao Ming','Male','1990-1-1')
print xiaoming.name

打印出来是Xiao Ming。

那么如果在定义这个类时，没想好他有什么属性时怎么办。

可以传递个列表，将要定义的东西传递进去。

class Person(object):
    def __init__(slef,*list):
        for attr in list:
            setattr(slef,attr,'None')


list = ['name','gender','birth','job','age']
xiaoming = Person(*list)
xiaoming.name = 'Xiao Ming'
xiaoming.age = 19
print xiaoming.name
print xiaoming.job
print xiaoming.age

执行结果：

Xiao Ming
None
19

Process finished with exit code 0

当然了，还可以使用字典，连初始属性也一块赋值了。

class Person(object):
    def __init__(slef,**dic):
        for attr,values in dic.items():
            setattr(slef,attr,values)


dic = {'name':'Xiao Ming','gender':'M','birth':'1990-1-1','job':'student','age':18}
xiaoming = Person(**dic)
print xiaoming.name
print xiaoming.job
print xiaoming.age

执行结果

Xiao Ming
student
18

Process finished with exit code 0