TypeError:'DictWriter'对象不可迭代

Question

我正在努力为非营利性募捐活动创建一个简短的简单程序,以便在客人办理登机手续时验证机票号码,以确保不会兑换重复的机票.我在Windows 10机器上运行Python 3.4.3.一旦程序完成,它将用于筹款活动中带触摸屏的Raspberry Pi.

我尝试了几种不同的方法来构建列表,保存它,并搜索重复项.理想情况下,列表将存储在CSV文件中,但纯文本或其他格式也可以.

你可以帮我解决追溯错误(TypeError:'DictWriter'对象不可迭代),因为循环函数根据存储在文件中的列表检查票证#,以确保没有重复的票据被兑换？

预先感谢您的帮助!

version = "v1.4"
fname="tickets.csv"
import csv
import datetime
import os.path
print("\nWelcome to TicketCheck", version)
extant = os.path.isfile(fname)
with open(fname, 'a', newline='') as csvfile:
    fieldnames = ['ticketid', 'timestamp']
    ticketwriter = csv.DictWriter(csvfile, fieldnames=fieldnames)
    if extant == False:
        ticketwriter.writeheader()
    while True:
        ticket = ""
        print("Please enter a ticket # to continue or type exit to exit:")
        ticket = str(input())
        if ticket == "":
            continue
        if ticket == "exit":
            break
        print("You entered ticket # %s." % (ticket))
        print("Validating ticket...")
        for row in ticketwriter:
            if row[0] == ticket:
                print("\n\n\n===== ERROR!!! TICKET # %s ALREADY CHECKED IN =====\n\n\n" % (ticket))
                continue
        time = datetime.datetime.now()
        print("Thank you for checking in ticket # %s at %s \n\n\n" % (ticket, time))
        print("Ticket is now validated.")
        ticketwriter.writerow({'ticketid': ticket, 'timestamp': time})
        csvfile.flush()
        continue
csvfile.close()
print("All your work has been saved in %s.\n Thank you for using TicketCheck %s \n" % (fname, version))

Answer 1

嗯,我想你可能有点过于复杂了!对于这样的事情,真的没有必要去解决所有麻烦.这是使用字典的好地方,对于只有两个输入的内容,id和签入时间,您可以轻松地制作.txt日志.我觉得这可能更像是你在寻找什么.

import time
go = True
while go:
    the_guestlist = {}
    the_ticket = input().strip()
    file = open('somefile.txt', 'r')
    for line in file:
        my_items = line.split(',')
        the_guestlist[my_items[0]] = my_items[1]
    file.close()
    if the_ticket in the_guestlist.keys():
        print("Sorry, that ticket has been entered at {}".format(the_guestlist[the_ticket]))
    elif the_ticket == 'exit':
        go = False
        print('Exiting...')
    else:
        the_guestlist[the_ticket] = '{}'.format(time.asctime())
        file = open('somefile.txt', 'a')
        file.write(the_ticket +','+the_guestlist[the_ticket]+'\n')
        file.close()