在类属性和今天的日期之后对字典进行排序

Question

我有一个类 Reminder 和字典 Events，我想根据今天的日期对字典进行排序。程序应该要求用户输入今天日期的 int 输入，然后打印字典中与这一天及以后相关的所有键。例如。它不应该打印已经过去的事件。   class Reminder:    self.name = name    self.date = date    self.reminder = reminder     event1 = Reminder('trip to vegas', 20130312, 'buy a suitcase')    event2 = Reminder('to do next month', 20190401, 'get a job')    event3 = Reminder('apply for college', 20190603, 'send in application'    event_dict = {}    event_dict[event1.name] = event1    event_dict[event2.name] = event2    event_dict[event3.name] = event3    todays date = int(input("Input today's date!"))所以现在当用户输入例如日期 20190328 时，程序不应该打印 event1，因为它已经过去了。如前所述，我希望在打印之前对事件 2 和 3 进行排序，以便首先打印下一个即将到来的日期。似乎没有必要对 2 个事件进行排序，但在整个代码中它将是更多的事件。

Answer 1

简单的实现：

class Reminder:

    def __init__(self, name, date, reminder):

        self.name = name

        self.date = date

        self.reminder = reminder 

    def __str__(self):

        return "Name: '{}' - Date: '{}' - Reminder: '{}'".format(self.name,

                                                           self.date,

                                                           self.reminder)

event1 = Reminder('trip to vegas', 20130312, 'buy a suitcase')

event2 = Reminder('to do next month', 20190401, 'get a job')

event3 = Reminder('apply for college', 20190603, 'send in application')

event_dict = {}

event_dict[event1.name] = event1

event_dict[event2.name] = event2

event_dict[event3.name] = event3

todays_date = 20180101

# implementation

events_sorted = sorted(event_dict.items(), key=lambda t: t[1].date)

events = [e[1] for e in events_sorted if e[1].date >= todays_date]

for e in events:

    print(e)

输出：

Name: 'to do next month' - Date: '20190401' - Reminder: 'get a job'

Name: 'apply for college' - Date: '20190603' - Reminder: 'send in application'

Answer 2

class Reminder(object):

    def __init__(self, name, date, reminder):

        self.name = name

        self.date = date

        self.reminder = reminder

event1 = Reminder('trip to vegas', 20130312, 'buy a suitcase')

event2 = Reminder('to do next month', 20190401, 'get a job')

event3 = Reminder('apply for college', 20190603, 'send in application')

event_dict = {}

    event_dict[event1.date] = event1

    event_dict[event2.date] = event2

    event_dict[event3.date] = event3

todays_date = int(input("Input today's date!"))

import operator

#filter passed dates

event_dict = {k: v for k, v in event_dict.items() if k > todays_date}

#sort dictionary

sorted_events = sorted(event_dict.items(), key=operator.itemgetter(0))

#print results

for item in sorted_events:

    print("trip name: " , item[1].name, "| trip date: ", item[1].date, "| trip reminder: ", item[1].reminder,' \n')

输出：

trip name:  to do next month | trip date:  20190401 | trip reminder:  get a job  

trip name:  apply for college | trip date:  20190603 | trip reminder:  send in application