Question

我的代码遇到AttributeError，我不知道如何解决

这是我的课程：

class Reservation:

    def __init__(self, passengerName, departureCity, destinationCity, dateOfTravel, timeOfTravel, numberOfTickets):
        self.passengerName = passengerName
        self.departureCity = departureCity
        self.destinationCity = destinationCity
        self.dateOfTravel = dateOfTravel
        self.timeOfTravel = timeOfTravel
        self.numberOfTickets = numberOfTickets

reservationList = list()

with open("reservation.txt", "w") as file:

    for reservation in reservationList:
        reservation.write(reservation.passengerName + "," + reservation.departureCity + "," + reservation.destinationCity +
                            "," + reservation.dateOfTravel + "," + reservation.timeOfTravel + "," +
                            str(reservation.numberOfTickets) + "\n")

    file.close()

File "C:/Users//Desktop/pld/ticket_reservation5.py", line 183, in <module>
    main()
  File "C:/Users//Desktop/pld/ticket_reservation5.py", line 176, in main
    reservation.write(reservation.passengerName + "," + reservation.departureCity + "," + reservation.destinationCity +
AttributeError: type object 'Reservation' has no attribute 'write'

Answer 1

您的各个Reservation对象没有写属性。您要调用文件的write方法，并使用对象的数据填充字符串。

with open("reservation.txt", "w") as file_:
    for reservation in reservationList:
        file_.write(reservation.passengerName + .... + "\n")

旁注，由于您使用的是上下文管理器（open（）为_），因此无需执行file.close()。经理会帮你做。

此外，file是内置函数，因此您不想覆盖它。您需要在变量名称后附加一个下划线，以区分变量as described in PEP8

Answer 2

reservation只是一个遍历列表ReservationList的迭代器，它没有定义任何写函数。有三种方法可以从文本文件读取数据。

read() : Returns the read bytes in form of a string. Reads n bytes, if no n specified, reads the entire file.

File_object.read([n])

readline() : Reads a line of the file and returns in form of a string.For specified n, reads at most n bytes. However, does not reads more than one line, even if n exceeds the length of the line.

File_object.readline([n])

readlines() : Reads all the lines and return them as each line a string element in a list.

  File_object.readlines()

下面是打开文件并读取文件的示例：

file1 = open("myfile.txt","r") 
print(file1.read()) 
print(file1.readline())

Answer 3

执行此操作，并确保列表中的最后一个字符串具有\n，以便每次其他用户输入用新行写的信息时都使用它：

with open("file_name.txt", 'a') as f: # "a" is used to append data to a file that is it
# does not delete previously written data instead appends to it also f is the variable 
# which stores the file and could be anything
    for reservation in reservationList:
        f.write(reservation)
    print("done")

AttributeError：类型对象“”没有属性“写入”

3 个答案: