尝试一种不同、 更多的波音方法。 这并不是一个答案, 而是一个选项。 经过三次编辑, 以考虑到对新功能的一些要求 。

import pickle

class TasksError(Exception):
    def __init__(self, value):
        self.value = value
    def __str__(self):
        return repr(self.value)

class Task(object):
    def __init__(self, task = () ):
        if task ==():
            raise TasksError( Empty task. )
        self.name = task[0]
        self.date = task[1]
        self.priority = task[2]

    def __str__(self):
        output =    Name: %s
Date: %s
Priority: %s
    % ( self.name,
        self.date,
        self.priority )
        return output

class Tasks(object):
    def __init__(self, container = []):
        self.container = [ Task(todo) for todo in container ]

    def find_by_priority(self, priority =  high ):
        # example method to seek and print high priority tasks
        # using this example, you will be able to conduct many
        # types of searches
        results = [ task
                   for task in self.container
                   if task.priority == priority ]
        return results

    def sort_by_date(self):
        # example method of how to sort, again, many other
        # ways of sorting can be implemented, this is just
        # to demonstrate the principle
        # for more info on sorting,
        # visit:  http://wiki.python.org/moin/HowTo/Sorting
        self.container = sorted(self.container,
                                key=lambda task: task.date)

    def add(self, task):
        if task ==   :
            raise TasksError( Empty task )
        self.container.append( Task(task) )

    def save(self):
        try:
            output = open( tasks.pkl ,  wb )
            pickle.dump(self.container, output)
            output.close()
        except:
            raise TasksError( Failed to save. )

    def load(self):
        try:
            pkl_file = open( tasks.pkl ,  rb )
            self.container = pickle.load(pkl_file)
            pkl_file.close()
        except:
            raise TasksError( Failed to load )

    def __str__(self):
        output =  
 .join( [ str(todo) for todo in self.container ] )
        return output

if __name__== "__main__":
    divider =  -  * 30 +  
 

    tasks = Tasks( [("birthday","20121111","high"),
                    ("christmas","20121225","medium"),
                    ("easter","20120405","low")] )
    print  Three original tasks:
 
    print tasks # prints out three tasks
    print divider

    tasks.add( ("new-task","20120320","high") )
    print  Three original plus one new task:
 
    print tasks # prints out four tasks
    print divider

    tasks.save() # pickles the task list and saves to disk

    tasks = Tasks( container = [] ) # creates a new, empty task list
    print  Empty task list:
 
    print tasks # prints out empty list
    print divider

    tasks.load() # loads the pickled list
    print  The four pickled tasks, reloaded:
 
    print tasks # prints out four tasks
    print divider

    while True:
        print divider,    Make your selection:
1. Add new task
2. Print all tasks
3. Save tasks
4. Load tasks from disk
5. Find high priority tasks
6. Sort by date
<ENTER> to quit
   
        try:
            menu_choice = int(input("Select a number from the menu: "))
        except:
            print  Goodbye! 
            break

        if menu_choice == 1:
            # note: no error checking here
            # even an empty input is accepted
            task = raw_input (">>> Task: ")
            date = raw_input (">>> Date as string YYYYMMDD: ")
            priority = raw_input (">>> Priority: ")
            todo = (task, date, priority)
            # note that here you should add a task
            # your method created a NEW task list
            # and replaced the old one
            tasks.add( todo )
            print tasks
        elif menu_choice == 2:
            print divider,  Printing all tasks 
            print tasks
        elif menu_choice == 3:
            print divider,  Saving all tasks 
            tasks.save()
        elif menu_choice == 4:
            print divider,  Loading tasks from disk 
            tasks.load()
        elif menu_choice == 5:
            print divider,  Finding tasks by priority 
            results = tasks.find_by_priority(priority= high )
            for result in results: print result
        elif menu_choice == 6:
            print divider,  Sorting by date 
            tasks.sort_by_date()
            print tasks

备注: 这是为展示您想要执行的许多特征和展示如何正确使用对象导向设计使您能够包罗每一项任务和任务清单并轻松地加以操作而制作的代码。 它也展示了使用泡菜作为原始问题中使用的文本文件执行的“ 音调” 替代物。 它也显示了按字段搜索和排序, 采用了两种简单的方法 。

如果您对这个项目是认真的, 您需要查看适当的数据库, 如 < a href=" http://docs. python. org/library/ sqlite3. html" rel=“ nofollow” >SQLite , 这样的人将无法用手可靠地执行搜索、 排序、 更新、 添加和删除记录。

假设您的名称、任务和优先事项是简单的 Python 对象,您可以用 ast.literal_eval 装入:

with open("tasks.txt", "r") as load_file:
    # no need for readlines, just loop over the file!
    tasks = [ast.literal_eval(ln) for ln in load_file]

然后绕过 tasks 来将对象放入 Tasks 对象中。 请注意, Tasks (add( task)) 将无法工作。 您需要有一个类型为 Tasks 的对象, 传递给 load (lets call it todo ), 并进行操作 。

for t in tasks:
    todo.add(t)