我想对字典键中的整数进行排序

Question

我创建了一个接收餐厅预订信息的程序，但我想按时间对预订进行排序。

该函数将-txt.file 作为参数，文件的内容遵循此结构 - "name", "time", "status"（"status" 是 CONFIRMED 或 CANCELLED）。它只应该显示CONFIRMED 预订并按"time" 对其进行排序。到目前为止，我已经能够显示预订，但我只是不知道如何对它们进行排序。

def show_reservations(filename):
    with open(filename) as file:
        content = file.readlines()

    for reservation in content:
        dictionary = {}
        if ", CONFIRMED" in reservation:
            dictionary.setdefault(reservation[:-12], "CONFIRMED")
            empty_list = []
            for k, v in dictionary.items():
                print(k)


print(show_reservations(blabla.txt))

-txt.file的任意内容：

MARTIN, 19, CONFIRMED
JULIE, 18, CONFIRMED
METTE, 17, CANCELLED

期望的输出：

JULIE, 18
MARTIN, 19

Answer 1

如果您将每个预订存储为具有两个键值对的字典，并将它们存储到列表中，则以下代码有效。

sorted() 允许您对预订列表进行排序。然后，您可以通过使用 lambda 指定排序因子来选择它。 :)

def show_reservations(filename):
    with open(filename) as file:
        content = file.readlines()

    # list to store confirmed reservations
    confirmed_list = []

    for reservation in content:
        # dict to be re-used to parse each reservation
        r = {}
        if ", CONFIRMED" in reservation:
            # splits each line to a list          e.g. ["JULIE", "16", "CONFIRMED"]
            reserv = reservation.split(",")
            # gets first element which is the name of customer and stores in dict
            # strip is to remove any leading/trailing whitespace
            r['name'] = reserv[0].strip()
            # gets second element which is the time of reservation and stores in dict
            r['time'] = reserv[1].strip()
            # appends dict to list
            confirmed_list.append(r)

    # sorts the list of confirmed reservations by time using lambda
    confirmed_list_s = sorted(confirmed_list, key=lambda k: k['time'])

    for r in confirmed_list_s:
        # prints out each reservation in sorted list
        row = ", ".join(val for key, val in r.items())
        print(row)

show_reservations("blabla.txt")

输出：

JO, 16
JULIE, 18
MARTIN, 19
CHARLIE, 20