如何将其中一个属性的类型更改为 int？

Question

为了了解一些背景信息，我试图让自己熟悉对象、类和 Python 上的属性。

class Plane:
def __init__(self,ModelName,brand,capacity):
    self.ModelName = ModelName
    self.brand = brand
    self.capacity = capacity

def intro_plane(self):
    print(
        "The name of the plane is " + self.ModelName + 
        ". It was released by " + self.brand +
        ". It has a capacity of " + self.capacity
        )
P1 = Plane("B737", "Boeing", 155)
P1.intro_plane()

我运行我在 VsCode 上的代码，这是结果：

TypeError: can only concatenate str (not "int") to str

Answer 1

capacity 是 int，不是 string。因此，当您添加到 print 函数时，您需要更改它的类型。

". It has a capacity of " + str(self.capacity)

Answer 2

如错误所述：

TypeError: can only concatenate str (not "int") to str

您不能连接字符串和整数。这是因为 2 个字符串之间的 + 连接了它们； + 在 2 个整数之间相加。

如果将它们混合使用，则会引发错误。

你可以这样做：

print(f"The name of the plane is {self.ModelName}. It was released by {self.brand}. It has a capacity of {self.capacity}")

这样，您就不必担心变量的数据类型

Answer 3

你可以这样使用 f-strings

print(f"The name of the plane is {self.ModelName}. It was released by {self.brand}.It has a capacity of {self.capacity}")

Answer 4

你的capacity变量已经归类为int，没有问题。

问题是如果不将 int 转换为 str 就无法打印它。

只需将 intro_plane 函数更改为：

def intro_plane(self):
    print(
        "The name of the plane is " + self.ModelName + 
        ". It was released by " + self.brand +
        ". It has a capacity of " + str(self.capacity)
        )

你应该很好

如何将其中一个属性的类型更改为 int？

How do I change one of my attributes' type to an int?

python

attributes

class

object