Question

我有一个像这样设置的课程

class Vehicle:
    def __init__(self, seats, wheels, engine):
        self.seats = seats
        self.wheels = wheels
        self.engine = engine

我得到了一个像这样的实例

porsche = Vehicle(2, 4, "gas")

我无法弄清楚如何使用实例“porsche”在屏幕上写出“__init__”部分中每个自我初始化的名称。

所需的输出是这样的句子：

"I have a Vehicle. It has seats, wheels, and an engine."

座椅轮和发动机来自班级。

我检索了Vehicle并使用它将其放入字符串：

porsche.__class__.__name__

但是对于我的生活无法弄清楚如何获得每个self.对象

Answer 1

您的问题似乎是询问如何知道对象上的属性名称。对于简单对象（没有插槽），它足以检查__dict__。所以从这样的事情开始：

def show(x):
    return "I have a {}. It has {}".format(type(x).__name__, ", ".join(x.__dict__))

然后

>>> show(Vehicle(1, 1, 1))
'I have a Vehicle. It has seats, wheels, engine'

Answer 2

您可以使用obj.__dict__来访问实例fields / members / data attributes。

你在找这样的东西吗？

class Vehicle:
    def __init__(self, seats, wheels, engine):
        self.seats = seats
        self.wheels = wheels
        self.engine = engine

    def description(self):
        # 'Vehicle'
        name = self.__class__.__name__

        # ['seats', 'wheels', 'engine']
        field_names = self.__dict__.keys()

        return "I have a %s. It has these fields: %s" % (
            name, ', '.join(field_names))


porsche = Vehicle(2, 4, "gas")
print(porsche.description())

输出：

I have a Vehicle. It has these fields: engine, wheels, seats

请注意，这些字段名称将以任意顺序排列（dicts在Python中是无序的），不一定按照__init__()中定义的顺序排列。

在python

2 个答案: