我可以在子定义中询问一个类的属性吗？答案

【问题标题】：Can I ask the attributes of a class in a sub-definition?我可以在子定义中询问一个类的属性吗？
【发布时间】：2016-12-26 13:20:26
【问题描述】：

圣诞快乐！

我试图生成一些代码，这些代码将使用用户提供的信息创建一种数据库。我可以使用input() 方法来定义我的实例变量吗？

class Compound:
def __init__(self, name, state, molecular_mass, concentration, concentration_measure):
    self.nome = name
    self.state = state
    self.mol_mass = molecular_mass
    self.conc = concentration
    self.measure = concentration_measure

def summary(self):
     return ('Your compound is {} it has a state of {} it has a molecular mass of {} g/mol and a concentration of {} and a measure of {}'
             .format(self.name, self.state, self.mol_mass, self.conc, self.measure))

def ask_compounds():
    self.nome = input("Name?")
    self.state = input('Solid or Liquid')
    self.mas_mol = input('Absolute number for molecular weight?')
    self.conc = input('Concentration?')
    self.measure = str(input('In M? In g/ml?'))

ask_compounds()

感谢您的帮助！

【问题讨论】：

标签： python python-3.x class variables input

【解决方案1】：

当然可以。 return 输入的值并用它们初始化Compound 类：

def ask_compounds():
    nome = input("Name?")
    state = input('Solid or Liquid')
    mas_mol = input('Absolute number for molecular weight?')
    conc = input('Concentration?')
    measure = input('In M? In g/ml?')
    return nome, state, mas_mol, conc, measure

inst = Compound(*ask_compounds())

或者，更好的是，将ask_compounds 设为为您创建实例的classmethod：

class Compound:
    def __init__(self, name, state, molecular_mass, concentration, concentration_measure):
        # snipped for brevity

    def summary(self):
         # snipped for brevity

    @classmethod
    def ask_compounds(cls):
        nome = input("Name?")
        state = input('Solid or Liquid')
        mas_mol = input('Absolute number for molecular weight?')
        conc = input('Concentration?')
        measure = input('In M? In g/ml?')
        return cls(nome, state, mas_mol, conc, measure)

inst = Compound.ask_compounds()

顺便说一句，您在__init__ 和ask_components 中使用nome，但在summary 中使用name，将两者之一更改为另一个。

【讨论】：