当字符串与属性具有相同的值时，如何将字符串转换为属性

Question

class Person:  
  __name = ""
  __contacts = [] 
  __age = 0
  __vaccination_state = False
  __health_state = True 
  __quarantine_state = True 
  __symptom = "symptomatic" 

  def __init__(self, name, contacts, age, vaccination_state, health_state, quarantine_state, symptom):
    self.__name = name
    self.__age = age 
    self.__contacts = contacts 
    self.__vaccination_state = vaccination_state
    self.__health_state = health_state
    self.__quarantine_state = quarantine_state
    self.__symptom = symptom 

  def GetName(self):
    return self.__name

  def GetAge(self):
    return self.__age
  
  def GetContacts(self):
    return self.__contacts

  def GetVaccination(self):
    return self.__vaccination_state

  def GetHealth(self):
    return self.__health_state

  def GetQuarantine(self):
    return self.__quarantine_state

  def GetSymptom(self):
    return self.__symptom
 
  def SetName(self, name):
    self.__name = name

  def SetAge(self, age):
    self.__age = age

  def SetAllContacts(self, contacts):
    self.__contacts = contacts 

  def AddSingleContact(self, contact):
    self.__contacts.append(contact)

  def SetVaccination(self, vaccination_state):
    self.__vaccination_state = vaccination_state

  def SetHealth(self, healthState):
    self.__health_state = healthState
    self.CheckPositive()

  def SetQuarantine(self, quarantine_state):
    self.__quarantine_state = quarantine_state
  
  def SetSymptom(self, symptom):
    self.__symptom = symptom 
  def CheckPositive(self):
    if self.__health_state == False: 
      self.__quarantine_state = True
      start = datetime.datetime.now()
      end = start + datetime.timedelta(10)
      for i in range(len(self.__contacts)):
        getattr(Person, self.GetContacts()[i]).SetQuarantine(True)
        print(self.GetContacts()[i], " and his/her close contacts have been notified.\n", "Quarantine starts at", start, "and ends at", end)
        for i in range(len(self.__contacts)):
          getattr(Person, self.GetContacts()[i]).SetQuarantine(True)

A = Person("A", ["Z"], 17, True, True, False, "NA")
Z = Person("Z", ["A"], 17, True, True, False, "NA")
A.SetHealth(False) 

SetQuarantine(True)是我要调用的类中的一个函数。self.GetContacts(i)的返回值是一个列表。因此，self.GetContacts()i是一个字符串，例如，"name“。但是，我希望获得一个属性，以便可以调用函数SetQuarantine(True)。该属性与字符串具有相同的值，但我不知道如何转换它。谢谢!

Answer 1

您的问题源于试图执行以下操作：getattr(Person, self.GetContacts()[i]).SetQuarantine(True)。您正在尝试访问一个不存在的Person.Z属性。因此Python会抛出一个错误。

要解决这个问题，您需要做两件事：

1. Don't (尝试)使用类级变量。当您希望在类的所有实例之间共享数据时，应该使用类级变量。由于Person的不同实例可以有不同的联系人，因此使用类级变量对Person的每个实例都没有意义，因此需要为每个联系人here.
2. In存储对Person对象的引用，而不是它们的名称。这让你可以直接设置一个密切接触者的隔离状态。(即使您要创建一个名称查找表，该表也无法处理两个同名人员)。

下面是一个修改后的CheckPositive函数以及一些修改过的驱动程序代码：

def CheckPositive(self):
  if self.__health_state == False: 
    self.__quarantine_state = True
    start = datetime.datetime.now()
    end = start + datetime.timedelta(10)
    for i in range(len(self.__contacts)):
      print(self.__contacts[i].GetName(), "has been notified.\n", "Quarantine starts at", start, "and ends at", end)
      self.__contacts[i].SetQuarantine(True)

A = Person("A", [], 17, True, True, False, "NA")
Z = Person("Z", [], 17, True, True, False, "NA")
A.AddSingleContact(Z)
Z.AddSingleContact(A)
A.SetHealth(False)