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在我使用 pyasn 创建的 Python 类之后，我希望看到通过文件传递值而不是创建对象并通过对象传递成员值的方式的可行性。字符串和数字的值类型将是在 excel 表中，这意味着其值不是另一个模式的所有参数都将在 excel 表中（模式表示像 Credit_card 这样的类）

from pyasn1.type import univ, char, namedtype, namedval, tag, constraint, useful


class Card_type(univ.Enumerated):
    pass


Card_type.namedValues = namedval.NamedValues(
    ('cb', 0),
    ('visa', 1),
    ('eurocard', 2),
    ('diners', 3),
    ('american-express', 4)
)


class Client(univ.Sequence):
    pass


Client.componentType = namedtype.NamedTypes(
    namedtype.NamedType('name', char.PrintableString().subtype(subtypeSpec=constraint.ValueSizeConstraint(1, 20)).subtype(implicitTag=tag.Tag(tag.tagClassContext, tag.tagFormatSimple, 0))),
    namedtype.OptionalNamedType('street', char.PrintableString().subtype(subtypeSpec=constraint.ValueSizeConstraint(1, 50)).subtype(implicitTag=tag.Tag(tag.tagClassContext, tag.tagFormatSimple, 1))),
    namedtype.NamedType('postcode', char.NumericString().subtype(subtypeSpec=constraint.ValueSizeConstraint(5, 5)).subtype(implicitTag=tag.Tag(tag.tagClassContext, tag.tagFormatSimple, 2))),
    namedtype.NamedType('town', char.PrintableString().subtype(subtypeSpec=constraint.ValueSizeConstraint(1, 30)).subtype(implicitTag=tag.Tag(tag.tagClassContext, tag.tagFormatSimple, 3))),
    namedtype.DefaultedNamedType('country', char.PrintableString().subtype(subtypeSpec=constraint.ValueSizeConstraint(1, 20)).subtype(implicitTag=tag.Tag(tag.tagClassContext, tag.tagFormatSimple, 4)).subtype(value="France"))
)


class Credit_card(univ.Sequence):
    pass


Credit_card.componentType = namedtype.NamedTypes(
    namedtype.NamedType('type', Card_type().subtype(implicitTag=tag.Tag(tag.tagClassContext, tag.tagFormatSimple, 0))),
    namedtype.NamedType('number', char.NumericString().subtype(subtypeSpec=constraint.ValueSizeConstraint(20, 20)).subtype(implicitTag=tag.Tag(tag.tagClassContext, tag.tagFormatSimple, 1))),
    namedtype.NamedType('expiry-date', char.NumericString().subtype(subtypeSpec=constraint.ValueSizeConstraint(6, 6)).subtype(implicitTag=tag.Tag(tag.tagClassContext, tag.tagFormatSimple, 2)))
)


class Payment_method(univ.Choice):
    pass


Payment_method.componentType = namedtype.NamedTypes(
    namedtype.NamedType('check', char.NumericString().subtype(subtypeSpec=constraint.ValueSizeConstraint(15, 15)).subtype(implicitTag=tag.Tag(tag.tagClassContext, tag.tagFormatSimple, 0))),
    namedtype.NamedType('credit-card', Credit_card().subtype(implicitTag=tag.Tag(tag.tagClassContext, tag.tagFormatConstructed, 1))),
    namedtype.NamedType('cash', univ.Null().subtype(implicitTag=tag.Tag(tag.tagClassContext, tag.tagFormatSimple, 2)))
)


class Order_header(univ.Sequence):
    pass


Order_header.componentType = namedtype.NamedTypes(
    namedtype.NamedType('reference', char.NumericString().subtype(subtypeSpec=constraint.ValueSizeConstraint(12, 12)).subtype(implicitTag=tag.Tag(tag.tagClassContext, tag.tagFormatSimple, 0))),
    namedtype.NamedType('date', char.NumericString().subtype(subtypeSpec=constraint.ValueSizeConstraint(8, 8)).subtype(implicitTag=tag.Tag(tag.tagClassContext, tag.tagFormatSimple, 1))),
    namedtype.NamedType('client', Client().subtype(implicitTag=tag.Tag(tag.tagClassContext, tag.tagFormatConstructed, 2))),
    namedtype.NamedType('payment', Payment_method().subtype(implicitTag=tag.Tag(tag.tagClassContext, tag.tagFormatConstructed, 3)))
)


class Order(univ.Sequence):
    pass


Order.componentType = namedtype.NamedTypes(
    namedtype.NamedType('header', Order_header().subtype(implicitTag=tag.Tag(tag.tagClassContext, tag.tagFormatConstructed, 0))),
    #namedtype.NamedType('items', univ.SequenceOf(componentType=Order_line()).subtype(implicitTag=tag.Tag(tag.tagClassContext, tag.tagFormatSimple, 1)))
)




a=Order()
a['header']['reference']='abcdefghixcv'
print a

#Output
Order:
 header=Order_header:
  reference=abcdefghixcv

我们可以通过诸如 excel 之类的文件来传递上述示例的 asn 的值吗？就像引用“abcdefghixcv”一样。

4

1 回答 1

0

问题：我们可以通过文件传递上述示例的 asn 值吗

给定以下数据，从任何文件中检索：

注意：对于这个例子，client_data它们保存在第二个文件中，用id == 12345!引用。这些data值已经分配给NamedTypeofclass Order['header']和class Client。

client_data = {'12345':{'name':'John', 'town':'New York'}}
data = {'reference': 'abc', 'date': '2018-10-03', 'client': '12345', 'payment': 'cash'}

为简洁起见，我已将您的类定义简化为唯一使用的部分。

class NumericString():
    def __init__(self, value):
        self.value = value
    def __str__(self):
        return self.value
    def __new__(arg):
        obj = object.__new__(NumericString)
        obj.__init__(arg)
        return obj

class Payment_method():
    def __init__(self, method):
        self.method = method
    def __str__(self):
        return self.method        
    def __new__(arg):
        obj = object.__new__(Payment_method)
        obj.__init__(arg)
        return obj

class Client():
    def __init__(self, data):
        self.data = data
    def __str__(self):
        return ", ".join(self.data.values())
    def __new__(id):
        obj = object.__new__(Client)
        obj.__init__(id)
        return obj

我假设asn1_schema可以从中检索以下class Order()，但为简单起见，我手动定义了它。 

asn1_schema = {'reference':NumericString, 'date':NumericString, 'client':Client, 'payment':Payment_method}

此示例绑定到 Data，这意味着 Dictdata知道Order['header']必须创建哪个类。因此不需要预定义Order。

# For simplicity, define order as a 'dict'
order = {'header':{}}

# Loop over the given data dict
for key in data:
    # Create a class maped from asn1_schema and pass data value
    if key == 'client':
        # For client pass data from 'client_data' using 'id'
        cls = asn1_schema[key].__new__(client_data[data[key]])
    else:
        cls = asn1_schema[key].__new__(data[key])

    # Update order header with this 'NamedType'
    order['header'][key] = cls

# Show the resulting order header
for key in order['header']:
    types = order['header'][key]
    print("{:10}:\t{:14}:\tvalue:{}".format(key, types.__class__.__name__, types))

输出：

date      : NumericString :     value:2018-10-03
reference : NumericString :     value:abc
client    : Client        :     value:John, New York
payment   : Payment_method:     value:cash

用 Python 测试：3.5.3

于 2018-10-03T12:27:47.643 回答