如何获得Python 3.7的新数据类字段类型?
问题描述：
Python 3.7引入了称为数据类的新功能.
Python 3.7 introduces new feature called data classes.
from dataclasses import dataclass
@dataclass
class MyClass:
id: int = 0
name: str = ''
在函数参数中使用类型提示(注释)时，可以使用inspect模块轻松获得带注释的类型.如何获取数据类字段类型?
When using type hints (annotation) in function parameters, you can easily get annotated types using inspect module. How can I get dataclass field types?
答
from dataclasses import dataclass
@dataclass
class MyClass:
id: int = 0
name: str = ''
myclass = MyClass()
myclass.__annotations__
>> {'id': int, 'name': str}
myclass.__dataclass_fields__
>> {'id': Field(name='id',type=<class 'int'>,default=0,default_factory=<dataclasses._MISSING_TYPE object at 0x0000000004EED668>,init=True,repr=True,hash=None,compare=True,metadata=mappingproxy({}),_field_type=_FIELD),
'name': Field(name='name',type=<class 'str'>,default='',default_factory=<dataclasses._MISSING_TYPE object at 0x0000000004EED668>,init=True,repr=True,hash=None,compare=True,metadata=mappingproxy({}),_field_type=_FIELD)}
在旁注中还有:
myclass.__dataclass_params__
>>_DataclassParams(init=True,repr=True,eq=True,order=False,unsafe_hash=False,frozen=False)