将对象实例列表从另一个 class 传递给方法

Question

我正在尝试传递另一个对象的 class 中的对象实例列表。当我直接这样做时——一切都在按预期进行。当他们传递列表时，它被包裹在一个元组中，它不起作用。比较输出：

报告:

Record: None, None, None

Record: E001, IPTV and telematics, at Nov 20: everything is sad

Record: E002, DPI, None

for report1:

None

(<main.Record object at 0x7f7b88d65908>, <main.Record object at 0x7f7b88d65940>, <main.Record object at 0x7f7b88d65978>)

None

这怎么可能？以及如何修复它？

class Ticket:
  tickets = []
  def __init__(self, id=None, group=None):
    self.id = id
    self.group = group
    self.tickets.append(self)

class Record(Ticket):  
  records = []
  def __init__(self, ticket=None, comment=None):
    self.ticket = ticket
    self.comment = comment
    self.records.append(self)

  def __str__(self):
    if self.ticket != None:
      return 'Record: ' +  '{0}, {1}, {2}'.format(self.ticket.id, self.ticket.group, self.comment)

class Report:  
  def __init__(self, *args):
    self.records = list(args)

  def show_all(self):
    for record in self.records:
      print(record)


if __name__ == '__main__':
  t1 = Ticket('E001', 'IPTV and telematics')
  t2 = Ticket('E002', 'DPI')
  rec1 = Record(Ticket())
  rec2 = Record(t1, 'at Nov 20: everything is sad')
  rec3 = Record(t2)

  report = Report(rec1,rec2,rec3)
  print(report.show_all())

  report1 = Report(tuple(rec1.records))
  print(report1.show_all())

Answer 1

在第一种情况下，您将 Record 实例作为单独的参数传递。在这种情况下，args 将是一个包含 3 个参数的元组。

在第二种情况下，您将传递一个参数，一个元组。与第一种情况一样，args 将是一个包含给定参数的元组：一个包含 Record 实例的元组。

如果您需要传递一个列表（或元组），目的是将每个列表项解释为一个单独的参数，use * to unpack the list:

report1 = Report(*rec1.records)

将对象实例列表从另一个 class 传递给方法

Passing a list of instances of object to the method from another class

object

instance

python-3.x