Python枚举转换
先看一个枚举类
from enum import Enum
class Color(Enum):
YELLOW = 1
GREEN = 2
BLACK = 3
RED = 4如何把a=1转换成枚举类型，很简单，直接使用方法Color(a)就可以
from enum import Enum
class Color(Enum):
YELLOW = 1
GREEN = 2
BLACK = 3
RED = 4
a = 1
print(Color(a))
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输出：
Color.YELLOW使用具体的值来访问枚举类型是一种方案，可以看做一个类型转换，但不是一个真正的类型转换。
注意:如果这个枚举类中不存在这个值是会报错的:
from enum import Enum
class Color(Enum):
YELLOW = 1
GREEN = 2
BLACK = 3
RED = 4
a = 6
print(Color(a))
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Traceback (most recent call last):
File "E:/projects/python_learn/eleven/c7.py", line 16, in
print(Color(a))
File "C:\Users\Administrator\AppData\Local\Programs\Python\Python36\lib\enum.py", line 291, in __call__
return cls.__new__(cls, value)
File "C:\Users\Administrator\AppData\Local\Programs\Python\Python36\lib\enum.py", line 533, in __new__
return cls._missing_(value)
File "C:\Users\Administrator\AppData\Local\Programs\Python\Python36\lib\enum.py", line 546, in _missing_
raise ValueError("%r is not a valid %s" % (value, cls.__name__))
ValueError: 6 is not a valid Color